Associating therapy adjustments with intended patient posture states

ABSTRACT

The disclosure described techniques for associating therapy adjustments with intended patient posture states. The techniques may include receiving a patient therapy adjustment to a parameter of a therapy program that defines electrical stimulation therapy delivered to the patient, identifying a posture state of the patient, and associating the patient therapy adjustment with the posture state when the patient therapy adjustment is within a range determined based on stored adjustment information for the identified posture state.

This application claims the benefit of U.S. Provisional Application No.61/080,002, titled, “POSTURE STATE DATA COLLECTION AND ASSOCIATEDPROGRAMMING” and filed on Jul. 11, 2008, the entire content of which isincorporated herein by reference.

TECHNICAL FIELD

The disclosure relates to medical devices and, more particularly, toprogrammable medical devices that deliver therapy.

BACKGROUND

A variety of medical devices are used for chronic, e.g., long-term,delivery of therapy to patients suffering from a variety of conditions,such as chronic pain, tremor, Parkinson's disease, epilepsy, urinary orfecal incontinence, sexual dysfunction, obesity, or gastroparesis. Asexamples, electrical stimulation generators are used for chronicdelivery of electrical stimulation therapies such as cardiac pacing,neurostimulation, muscle stimulation, or the like. Pumps or other fluiddelivery devices may be used for chronic delivery of therapeutic agents,such as drugs. Typically, such devices provide therapy continuously orperiodically according to parameters contained within a program. Aprogram may comprise respective values for each of a plurality ofparameters, specified by a clinician.

In some cases, the patient may be allowed to activate and/or modify thetherapy delivered by the medical device. For example, a patient may beprovided with a patient programming device. The patient programmingdevice communicates with a medical device to allow the patient toactivate therapy and/or adjust therapy parameters. For example, animplantable medical device (IMD), such as an implantableneurostimulator, may be accompanied by an external patient programmerthat permits the patient to activate and deactivate neurostimulationtherapy and/or adjust the intensity of the delivered neurostimulation.The patient programmer may communicate with the IMD via wirelesstelemetry to control the IMD and/or retrieve information from the IMD.

SUMMARY

In general, the disclosure provides a method for associating detectedpatient therapy adjustments with a posture state and storing theassociations. The system may determine the associations intended by thepatient through implementation of a posture search timer and a posturestability timer that track therapy adjustments and posture state changesin real time. Since some patients make therapy adjustments inanticipation of changing to a different posture state, instead of makingchanges once in the desired posture state, these timers may allow thesystem to correctly associate therapy adjustments to posture states madebefore the patient engaged in the posture state or current posturestates.

The associations of the therapy adjustments with posture states may beused in a record mode for later review. An implantable medical device(IMD) or external programmer may be configured to store multiple therapyadjustments for each posture state and allow a user to find efficacioustherapy based upon review of the associations stored for each posturestate. The recorded therapy adjustments may be presented as a range oftherapy parameters to focus the user on acceptable therapy parametersfor each of the posture states. In this manner, the patient and/orphysician may be able to fine-tune stimulation therapy for the patient.

The associations of therapy adjustments with posture states also mayallow the user to set nominal therapy parameters for a plurality ofprograms with a single action, such as one click of a confirmation inputon an input device of a user interface. The nominal therapy parametersmay be previously adjusted values for therapy parameters that supporteffective therapy. A single action, such as a one-click confirmation,prevents the user from having to set the therapy parameters for eachprogram of each group in each posture state on an individual basis.

Further, in some examples, the system may provide a suggested therapyparameter for each of the plurality of individual programs based uponthe therapy adjustment information that includes the associations. Thesystem may implement a guided programming process that is used togenerate the suggested therapy parameters and limit programming timeneeded from the clinician.

In addition, the system may be capable of only associating therapyadjustments that have been intended by the patient for only a particularposture state. If the system recognizes that a received therapyadjustment is outside of a historical range of the prior stored therapyadjustments, the system may not make the association of the therapyadjustment to the posture state. However, the system may prompt the userto confirm the association and only make the association once theconfirmation is received.

In one example, the disclosure provides a method comprising detecting aplurality of patient adjustments to electrical stimulation therapydelivered to a patient during multiple instances of a sensed posturestate, associating the detected patient adjustments with the sensedposture state of the patient, and storing the associations of thedetected patient adjustments with the sensed posture state in a memory.

In another example, the disclosure provides a system comprising an inputdevice that receives a plurality of patient adjustments to electricalstimulation therapy delivered to a patient during multiple instances ofa sensed posture state, a processor that associates the received patientadjustments with the sensed posture state of the patient, and a memorythat stores the associations of the received patient adjustments withthe sensed posture state in a memory.

In another example, the disclosure provides an external programmer foran implantable medical device, the programmer comprising an input devicethat receives a plurality of patient adjustments to electricalstimulation therapy delivered to the patient by the implantable medicaldevice during multiple instances of a sensed posture state, a telemetryinterface that receives a sensed posture state from the implantablemedical device and transmits the received patient adjustments to theimplantable medical device, a processor that associates the receivedpatient adjustments with the sensed posture state of the patient, and amemory that stores the associations of the received adjustments with thesensed posture state in a memory.

In another example, the disclosure provides An implantable medicaldevice comprising a stimulation generator that delivers electricalstimulation therapy to a patient, a posture sensing module that senses aposture state of the patient, a telemetry interface that receivespatient adjustments to the electrical stimulation therapy from anexternal programmer during multiple instances of a plurality of sensedpostured states, a processor that associates the received adjustmentswith a sensed posture state of the patient, and a memory that stores theassociations of the received adjustments with the sensed posture statein a memory.

In another example, the disclosure provides a method comprisingdetecting a patient adjustment to electrical stimulation therapydelivered to the patient, sensing a posture state of the patient, andassociating the detected adjustment with the sensed posture state if thesensed posture state is sensed within a first period following thedetection of the adjustment and if the sensed posture state does notchange during a second period following the sensing of the sensedposture state.

In another example, the disclosure provides a system comprising a userinterface configured to detect a patient adjustment to electricalstimulation therapy delivered to the patient, a posture state modulethat senses a posture state of the patient, and a processor thatassociates the detected adjustment with the sensed posture state if thesensed posture state is sensed within a first period following thedetection of the adjustment and if the sensed posture state does notchange during a second period following the sensing of the sensedposture state.

In another example, the disclosure provides an external programmer foran implantable medical device comprising a user interface that receivespatient adjustments to electrical stimulation therapy delivered to thepatient by the implantable medical device, a telemetry interface thatreceives a sensed posture state from the implantable medical device andtransmits the received adjustments to the implantable medical device, aprocessor that associates the detected adjustment with the sensedposture state if the sensed posture state is sensed within a firstperiod following the detection of the adjustment and if the sensedposture state does not change during a second period following thesensing of the sensed posture state, and a memory that stores theassociations of the received adjustments with the sensed posture statein a memory.

In another example, the disclosure provides an implantable medicaldevice comprising a stimulation generator that delivers electricalstimulation therapy to a patient, a telemetry interface that receivespatient adjustments to the electrical stimulation therapy from anexternal programmer, a posture sensing module that senses a posturestate of the patient, a processor that associates the receivedadjustments with the sensed posture state if the sensed posture state issensed within a first period following the receiving of the adjustmentand if the sensed posture state does not change during a second periodfollowing the sensing of the sensed posture state, and a memory thatstores the associations of the received adjustments with the sensedposture state in a memory.

In another example, the disclosure provides a method comprisingpresenting therapy adjustment information to a user via a userinterface, wherein the therapy adjustment information includes one ormore therapy adjustments made by a patient to at least one stimulationparameter of one or more stimulation therapy programs for one or morepatient posture states, receiving input from the user that selects oneor more nominal therapy parameters for each of the therapy programs andfor each of the posture states based on the therapy adjustmentinformation, and setting the selected nominal therapy parameters foreach of the therapy programs and posture states for use in deliveringstimulation therapy to the patient.

In another example, the disclosure provides a system comprising a memorythat stores therapy adjustment information that includes one or moretherapy adjustments made by a patient to at least one stimulationparameter of one or more stimulation therapy programs for one or morepatient posture states, a user interface that presents the therapyadjustment information to a user and receives input from the user thatselects one or more nominal therapy parameters for each of the therapyprograms and for each of the posture states based on the therapyadjustment information, and a processor that sets the selected nominaltherapy parameters for each of the therapy programs and posture statesfor use in delivering stimulation therapy to the patient.

In another example, the disclosure provides an external programmer foran implantable medical device comprising a user interface that presentstherapy adjustment information to a user via a user interface, whereinthe therapy adjustment information includes one or more therapyadjustments made by a patient to at least one stimulation parameter ofone or more stimulation therapy programs for one or more patient posturestates, and receives input from the user that selects one or morenominal therapy parameters for each of the therapy programs and for eachof the posture states based on the therapy adjustment information, and aprocessor that sets the selected nominal therapy parameters for each ofthe therapy programs and posture states for use in deliveringstimulation therapy to the patient.

In another example, the disclosure provides a method comprisingreceiving therapy adjustment information that includes therapyadjustments made by a patient to at least one parameter of one or morestimulation therapy programs for one or more patient posture states,generating one or more suggested therapy parameters for one or more ofthe stimulation therapy programs based on the therapy adjustmentinformation, and presenting the suggested therapy parameters to a user.

In another example, the disclosure provides a programming device for animplantable medical device, the programmer comprising a processorconfigured to generate one or more suggested therapy parameters for oneor more stimulation therapy programs delivered by the implantablemedical device based on therapy adjustment information, wherein thetherapy adjustment information includes therapy adjustments made by apatient to at least one parameter of the stimulation therapy programsfor one or more patient posture states, and a user interface thatpresents the suggested therapy parameters to a user and receives inputfrom the user selecting at least some of the suggested therapyparameters, wherein the processor sets the selected suggested therapyparameters to at least partially define the respective therapy programsfor the respective posture states.

In another example, the disclosure provides a method comprisingreceiving a patient therapy adjustment to a parameter of a therapyprogram that defines electrical stimulation therapy delivered to thepatient, identifying a posture state of the patient, and associating thepatient therapy adjustment with the posture state when the patienttherapy adjustment is within a range determined based on storedadjustment information for the identified posture state.

In another example, the disclosure provides a system comprising a userinterface that receives a patient therapy adjustment to a parameter of atherapy program that defines electrical stimulation therapy delivered tothe patient, and a processor that identifies a posture state of thepatient, associates the patient therapy adjustment with the posturestate when the patient therapy adjustment is within a range determinedbased on stored adjustment information for the identified posture state.

The details of one or more aspects of the disclosure are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages will be apparent from the description anddrawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a conceptual diagram illustrating an implantable stimulationsystem including two implantable stimulation leads.

FIG. 1B is a conceptual diagram illustrating an implantable stimulationsystem including three implantable stimulation leads.

FIG. 1C is a conceptual diagram illustrating an implantable drugdelivery system including a delivery catheter.

FIG. 2 is a conceptual diagram illustrating an example patientprogrammer for programming stimulation therapy delivered by animplantable medical device.

FIG. 3 is a conceptual diagram illustrating an example clinicianprogrammer for programming stimulation therapy delivered by animplantable medical device.

FIG. 4 is a functional block diagram illustrating various components ofan implantable electrical stimulator.

FIG. 5 is a functional block diagram illustrating various components ofan implantable drug pump.

FIG. 6 is a functional block diagram illustrating various components ofan external programmer for an implantable medical device.

FIG. 7 is a block diagram illustrating an example system that includesan external device, such as a server, and one or more computing devicesthat are coupled to an implantable medical device and externalprogrammer shown in FIGS. 1A-1C via a network.

FIGS. 8A-8C are conceptual illustrations of posture cones that may beused to define a posture state of a patient based on signals sensed by aposture state sensor.

FIG. 9 is a conceptual diagram illustrating an example user interface ofa patient programmer for delivering therapy information to the patient.

FIG. 10 is a conceptual diagram illustrating an example user interfaceof a patient programmer for delivering therapy information that includesposture information to the patient.

FIGS. 11A and 11B are conceptual diagrams illustrating an example userinterface for orienting an implantable medical device with patientposture states prior to diagnostic or therapy use of the implantablemedical device.

FIGS. 12A and 12B are conceptual diagrams illustrating an example userinterface to determine orientation of an implantable medical devicewithout requiring each posture state for orientation.

FIG. 13 is a conceptual diagram illustrating example posture search andposture stability timers with only one posture state.

FIG. 14 is a conceptual diagram illustrating example posture search andposture stability timers with one change in posture state.

FIG. 15 is a conceptual diagram illustrating example posture search andposture stability timers with two changes in posture states.

FIG. 16 is a conceptual diagram illustrating example posture search andposture stability timers with the last posture state change occurringoutside of the posture search timer.

FIG. 17 is a flow diagram illustrating an example method for associatinga received therapy adjustment with a posture state.

FIG. 18 is a conceptual diagram illustrating an example user interfacefor initiating the record mode that stores therapy adjustments for eachposture state.

FIG. 19 is a conceptual diagram illustrating an example user interfaceshowing stored adjustment information and allowing one-clickprogramming.

FIG. 20 is a conceptual diagram illustrating an example user interfaceshowing user selection of a program group.

FIG. 21 is a conceptual diagram illustrating an example user interfaceshowing user selection of a posture state.

FIG. 22 is a conceptual diagram illustrating an example user interfaceshowing stored adjustment information for all posture states of aprogram group to allow one-click programming.

FIG. 23 is a conceptual diagram illustrating an example user interfaceshowing detailed adjustment information associated with FIG. 22.

FIGS. 24A and 24B are conceptual diagrams illustrating an example userinterface showing maximum and minimum therapy adjustments associated foreach posture state.

FIG. 25A is a conceptual diagram illustrating an example user interfaceshowing quantified therapy adjustments for each posture state.

FIG. 25B is a conceptual diagram illustrating an example user interfaceshowing quantified therapy adjustments for each posture state in allgroups and a specified group.

FIG. 26 is a conceptual diagram illustrating an example user interfaceshowing stored adjustment information for all posture states of aprogram group to allow one-click programming.

FIG. 27 is a flow diagram illustrating an example method for associatingtherapy adjustments with posture states during a record mode.

FIG. 28 is a flow diagram illustrating an example method for displayingsuggested parameters and receiving an accept input from the user forone-click programming.

FIG. 29 is a conceptual diagram illustrating an example user interfacepresenting suggested therapy parameters for each program of a programgroup in guided programming.

FIG. 30 is a conceptual diagram illustrating an example user interfaceshowing different guided algorithms selectable by the user for guidedprogramming.

FIG. 31 is a flow diagram illustrating an example method for generatinga suggested therapy parameter for each therapy program and receiving aconfirmation input from the user.

FIG. 32 is a flow diagram illustrating an example method for correctinga therapy adjustment associated with an unintended posture state.

DETAILED DESCRIPTION

In some medical devices that deliver electrical stimulation therapy,therapeutic efficacy may change as the patient changes between differentposture states. In general, a posture state may refer to a patientposture or a combination of posture and activity. For example, someposture states, such as an upright posture state, may be sub-categorizedas upright and active or upright and inactive. Other posture states,such as lying down posture states, may or may not have an activitycomponent. Efficacy may refer, in general, to a combination of completeor partial alleviation of symptoms alone, or in combination with somedegree of undesirable side effects.

Changes in posture state may cause changes in efficacy due to changes indistances between electrodes or other therapy delivery elements, e.g.,due to temporary migration of leads or catheters caused by forces orstresses associated with different postures of the patient, or fromchanges in compression of patient tissue in different posture states.Also, posture state changes may present changes in symptoms or symptomlevels, e.g., pain level. To maintain therapeutic efficacy, it may bedesirable to adjust therapy parameters based on different posturesand/or activities engaged by the patient to maintain effectivestimulation therapy. Therapy parameters may be adjusted individually anddirectly or by selecting different programs or groups of programsdefining different sets of therapy parameters.

A change in efficacy due to changes in posture state may require thepatient to continually manage therapy by manually adjusting certaintherapy parameters, such as amplitude, pulse rate, pulse width,electrode combination, or electrode polarity, or selecting differenttherapy programs to achieve more efficacious therapy throughout manydifferent posture states. In some cases, a medical device may employ aposture state detector that detects the patient posture state. Themedical device may subsequently adjust therapy parameters in response todifferent posture states. Therapy adjustments in response to differentposture states may be fully automatic, semi-automatic in the sense thata user may provide approval of proposed changes, or user-directed in thesense that the patient may manually adjust therapy based on the posturestate indication.

Stimulation therapy may be provided to a patient in order to relievesymptoms from any number of conditions and diseases. An implantablemedical device (IMD) that delivers stimulation therapy may also employ aposture state sensor that is configured to sense which posture state thepatient is engaged. The sensed posture state may then be associated withtherapy adjustments made manually by the patient, i.e., patientadjustments, during the sensed posture state or multiple instances ofthe sensed posture state to allow a user to review the associations andmodify stimulation parameters to better treat the patient.

When the patient makes a patient therapy adjustment, i.e., a change toone of the stimulation parameters that define the stimulation therapy,the therapy adjustment is intended for a particular posture state.Although most therapy adjustments may be made and intended for theposture state currently occupied by the patient, sometimes the patientmay anticipate the next posture state and make the manual patientadjustment prior to moving to the intended posture state. Therefore, thesystem must associate the therapy adjustment with the anticipatedposture state that the patient intends to occupy.

To accomplish this association, the system may implement a posturesearch timer for each instance of a sensed posture state, i.e., eachtime that a posture state is sensed. The posture search timer may have asearch period and a posture stability timer may have a stability periodthat, when used together, allow the system to associate a therapyadjustment to a later posture state. The therapy adjustment is onlyassociated with the final posture state if the final posture state issensed within the search period of the posture state timer and continuesfor at least the stability period of the posture stability timer. Inthis sense, the system may correctly associate therapy parameters withposture states that the patient intended without making unintendedassociations.

In another example, the system may enter a record mode that storesassociations between therapy adjustments and posture states. The recordmode may permit monitoring of patient therapy adjustments for multipleposture states over a period of time to aid in selection of automatedtherapy adjustments for use in delivery of posture-responsive therapy.Even when a therapy adjustment is made for a therapy program and posturestate in which a therapy adjustment has already been made, allpreviously stored therapy adjustments may be maintained in memory topopulate the therapy adjustment information used in the record mode.Association of a therapy adjustment with a posture state may permit auser to identify the posture state for which the patient intended tomake the therapy adjustment.

An external programmer, such as a clinician programmer, may present thetherapy adjustment information to the user via an output device of auser interface. For example, the presented therapy adjustmentinformation may include minimum and/or maximum amplitude values from thetherapy adjustments, the average amplitude value of the therapyadjustments, or the quantified number of therapy adjustments for eachtherapy program in each posture state. The user may then modify therapyparameters for one or more programs or program groups of programs basedupon the presented information.

In other examples, the associations of therapy adjustments to posturestates also may allow the user to quickly program stimulation parametersfor therapy. An output device of the user interface of an externalprogrammer, e.g., the clinician programmer, may present stimulationparameters, or a nominal therapy parameter, for each of the plurality oftherapy programs from the therapy adjustments. The nominal therapyparameter may be a therapy parameter selected from the therapyadjustments stored in the IMD. The nominal therapy adjustment may not beweighted or calculated according to an algorithm. An input device of theuser interface may then allow the user to set the presented nominaltherapy parameter to all therapy programs by receiving just oneconfirmation input from the user. The nominal therapy parameter may bethe minimum amplitude of the therapy adjustments or the last therapyadjustments used, for example.

An output device of the user interface may also present a suggestedtherapy parameter based upon the therapy adjustments for each of theindividual therapy programs. The user may then select or confirm thesuggested therapy parameters for all of the plurality of therapyprograms with one confirmation input via an input device of the userinterface. Specifically, the suggested therapy parameter may begenerated from a guided algorithm created to find the most efficacioustherapy for the patient, instead of just a therapy adjustment stored inthe IMD. The guided algorithm may implement any one or more of weightedaverages, therapy adjustment trends, safe guards to protect againstoverstimulation, or any other factors. In this manner, the clinician maynot be burdened with the time needed to find the most efficacioustherapy parameters for the patient, and each time the patient enters adifferent posture state, the therapy programs will deliver therapy withthe most appropriate therapy parameters.

An input device and output device may be referred to collectively as auser interface. In some cases, the input and output devices may beassociated with different devices. For example, in some cases, therapyadjustments may be made by a patient via a user interface associatedwith a patient programmer. Some information, such as informationrelating to therapy adjustments, postures, and the like, may bepresented to a user via a clinician programmer or other device. In othercases, the input and output device may be associated with the sameprogrammer. For example, a clinician programmer may present informationrelating to therapy adjustments and postures via an output device, andreceive programming information from a user via an input device.

In addition, a programmer may be capable of associating therapyadjustments that have been intended by the patient for only a particularposture state. If the programmer recognizes that a received therapyadjustment is outside of a historical range of the prior stored therapyadjustments, the programmer may not make the association of the therapyadjustment to the posture state. However, the programmer may prompt theuser to confirm the association and only make the association once theconfirmation is received.

Various aspects of the techniques described in this disclosure may beprovided in an implantable medical device (IMD), an external programmerfor the IMD or a combination of both. For example, processors in theimplantable medical device and external programmer may perform variousfunctions such as recording of therapy adjustment associations withparticular programs and posture states.

In cases where association is performed by the IMD, therapy adjustmentsmay be transmitted to the IMD from the programmer for not onlyadjustment of therapy delivered by the IMD, but also for use by the IMDin associating the adjustments with pertinent programs and posturesstates to support a recording mode for collection of such associations.In cases where association is performed by the external programmer,sensed posture states may be transmitted to the programmer from the IMDfor not only recording and presentation of posture states, but also foruse by the programmer in associating the adjustments with pertinentprograms and postures states to support a recording mode for collectionof such associations.

Hence, in many instances, functionality described in this disclosure maybe performed by the IMD, the programmer, or a combination of both.Therefore, examples that described particular functionality in the IMDor programmer should not be considered limiting of the techniques,devices and systems, as broadly described in this disclosure.

FIG. 1A is a schematic diagram illustrating an implantable stimulationsystem 10 including a pair of implantable electrode arrays in the formof stimulation leads 16A and 16B. Although the techniques described inthis disclosure may be generally applicable to a variety of medicaldevices including external and implantable medical devices (IMDs),application of such techniques to IMDs and, more particularly,implantable electrical stimulators such as neurostimulators will bedescribed for purposes of illustration. More particularly, thedisclosure will refer to an implantable spinal cord stimulation (SCS)system for purposes of illustration, but without limitation as to othertypes of medical devices.

As shown in FIG. 1A, system 10 includes an IMD 14 and externalprogrammer 20 shown in conjunction with a patient 12. In the example ofFIG. 1A, IMD 14 is an implantable electrical stimulator configured forspinal cord stimulation (SCS), e.g., for relief of chronic pain or othersymptoms. Again, although FIG. 1A shows an implantable medical device,other embodiments may include an external stimulator, e.g., withpercutaneously implanted leads. Stimulation energy is delivered from IMD14 to spinal cord 18 of patient 12 via one or more electrodes ofimplantable leads 16A and 16B (collectively “leads 16”). In someapplications, such as spinal cord stimulation (SCS) to treat chronicpain, the adjacent implantable leads 16 may have longitudinal axes thatare substantially parallel to one another.

Although FIG. 1A is directed to SCS therapy, system 10 may alternativelybe directed to any other condition that may benefit from stimulationtherapy. For example, system 10 may be used to treat tremor, Parkinson'sdisease, epilepsy, urinary or fecal incontinence, sexual dysfunction,obesity, or gastroparesis. In this manner, system 10 may be configuredto provide therapy taking the form of deep brain stimulation (DBS),pelvic floor stimulation, gastric stimulation, or any other stimulationtherapy. In addition, patient 12 is ordinarily a human patient.

Each of leads 16 may include electrodes (not shown in FIG. 1), and theparameters for a program that controls delivery of stimulation therapyby IMD 14 may include information identifying which electrodes have beenselected for delivery of stimulation according to a stimulation program,the polarities of the selected electrodes, i.e., the electrodeconfiguration for the program, and voltage or current amplitude, pulserate, and pulse width of stimulation delivered by the electrodes.Delivery of stimulation pulses will be described for purposes ofillustration. However, stimulation may be delivered in other forms suchas continuous waveforms. Programs that control delivery of othertherapies by IMD 14 may include other parameters, e.g., such as dosageamount, rate, or the like for drug delivery.

In the example of FIG. 1A, leads 16 carry one or more electrodes thatare placed adjacent to the target tissue of the spinal cord. One or moreelectrodes may be disposed at a distal tip of a lead 16 and/or at otherpositions at intermediate points along the lead. Leads 16 may beimplanted and coupled to IMD 14. Alternatively, as mentioned above,leads 16 may be implanted and coupled to an external stimulator, e.g.,through a percutaneous port. In some cases, an external stimulator maybe a trial or screening stimulation that used on a temporary basis toevaluate potential efficacy to aid in consideration of chronicimplantation for a patient. In additional embodiments, IMD 14 may be aleadless stimulator with one or more arrays of electrodes arranged on ahousing of the stimulator rather than leads that extend from thehousing.

The stimulation may be delivered via selected combinations of electrodescarried by one or both of leads 16. The target tissue may be any tissueaffected by electrical stimulation energy, such as electricalstimulation pulses or waveforms. Such tissue includes nerves, smoothmuscle, and skeletal muscle. In the example illustrated by FIG. 1A, thetarget tissue is spinal cord 18. Stimulation of spinal cord 18 may, forexample, prevent pain signals from traveling through the spinal cord andto the brain of the patient. Patient 12 may perceive the interruption ofpain signals as a reduction in pain and, therefore, efficacious therapyresults.

The deployment of electrodes via leads 16 is described for purposes ofillustration, but arrays of electrodes may be deployed in differentways. For example, a housing associated with a leadless stimulator maycarry arrays of electrodes, e.g., rows and/or columns (or otherpatterns), to which shifting operations may be applied. Such electrodesmay be arranged as surface electrodes, ring electrodes, or protrusions.As a further alternative, electrode arrays may be formed by rows and/orcolumns of electrodes on one or more paddle leads. In some embodiments,electrode arrays may include electrode segments, which may be arrangedat respective positions around a periphery of a lead, e.g., arranged inthe form of one or more segmented rings around a circumference of acylindrical lead.

In the example of FIG. 1A, stimulation energy is delivered by IMD 14 tothe spinal cord 18 to reduce the amount of pain perceived by patient 12.As described above, IMD 14 may be used with a variety of different paintherapies, such as peripheral nerve stimulation (PNS), peripheral nervefield stimulation (PNFS), DBS, cortical stimulation (CS), pelvic floorstimulation, gastric stimulation, and the like. The electricalstimulation delivered by IMD 14 may take the form of electricalstimulation pulses or continuous stimulation waveforms, and may becharacterized by controlled voltage levels or controlled current levels,as well as pulse width and pulse rate in the case of stimulation pulses.

In some examples, IMD 14 may deliver stimulation therapy according toone or more programs. A program defines one or more parameters thatdefine an aspect of the therapy delivered by IMD 14 according to thatprogram. For example, a program that controls delivery of stimulation byIMD 14 in the form of pulses may define a voltage or current pulseamplitude, a pulse width, a pulse rate, for stimulation pulses deliveredby IMD 14 according to that program. Moreover, therapy may be deliveredaccording to multiple programs, wherein multiple programs are containedwithin each of a multiple of groups.

Each program group may support an alternative therapy selectable bypatient 12, and IMD 14 may deliver therapy according to the multipleprograms. IMD 14 may rotate through the multiple programs of the groupwhen delivering stimulation such that numerous conditions of patient 12are treated. As an illustration, in some cases, stimulation pulsesformulated according to parameters defined by different programs may bedelivered on a time-interleaved basis. For example, a group may includea program directed to leg pain, a program directed to lower back pain,and a program directed to abdomen pain. In this manner, IMD 14 may treatdifferent symptoms substantially simultaneously.

During use of IMD 14 to treat patient 12, movement of patient 12 amongdifferent posture states may affect the ability of IMD 14 to deliverconsistent efficacious therapy. For example, leads 16 may migrate towardIMD 14 when patient 12 bends over, resulting in displacement ofelectrodes and possible disruption in delivery of effective therapy.Stimulation energy transferred to target tissue may be reduced due toelectrode migration, causing reduced efficacy in terms of relief ofsymptoms such as pain. As another example, leads 16 may be compressedtowards spinal cord 18 when patient 12 lies down. Such compression maycause an increase in the amount of stimulation energy transferred totarget tissue. In this case, the amplitude of stimulation therapy mayneed to be decreased to avoid causing patient 12 additional pain orunusual sensations, which may be considered undesirable side effectsthat undermine overall efficacy.

Also, posture state changes may present changes in symptoms or symptomlevels, e.g., pain level. In some examples, to avoid interruptions ineffective therapy, IMD 14 may include a posture state module thatdetects the patient posture state. The IMD automatically adjustsstimulation according to the detected posture state. For example, theposture state module may include one or more accelerometers that detectwhen patient 12 occupies a posture state in which it is appropriate todecrease the stimulation amplitude, e.g., when patient 12 lies down. TheIMD may automatically reduce stimulation amplitude so that patient 12does not manually have to do so. Example posture states may include“Upright,” “Upright and Active,” “Lying Down,” and so forth.

As will be described in greater detail below, in some examples, IMD 14may be configured to automatically decrease stimulation amplitude whenit detects that patient 12 lies down. The amplitude adjustment may beconfigured to be decreased at a rate suitable to prevent undesirableeffects, e.g., such as the effects due to the compression of leads 16towards spinal cord 18 when patient 12 lies down. In some examples, IMD14 may be configured to decrease the stimulation amplitude to a suitableamplitude value substantially immediately upon detection by IMD 14 thatpatient 12 is lying down. In other examples, the stimulation amplitudemay not be decreased substantially immediately by IMD 14 upon detectionof patient 12 lying down, but instead IMD 14 may decrease thestimulation amplitude to a suitable amplitude level at a rate of changethat is suitable to prevent patient 12 from experiencing undesirablestimulation effects, e.g., due to increased transfer of stimulationenergy in the changed anatomical position. In some examples, IMD 14 maysubstantially instantaneously decrease the stimulation amplitude to asuitable amplitude value when IMD detects that patient 12 is lying down.

Many other examples of reduced efficacy due to increased coupling ordecreased coupling of stimulation energy to target tissue may occur dueto changes in posture and/or activity level associated with patientposture state. To avoid or reduce possible disruptions in effectivetherapy due to posture state changes, IMD 14 may include a posture statemodule that detects the posture state of patient 12 and causes the IMD14 to automatically adjust stimulation according to the detected posturestate. For example, a posture state module may include a posture statesensor, such as an accelerometer, that detects when patient 12 liesdown, stands up, or otherwise changes posture.

In response to a posture state indication by the posture state module,IMD 14 may change a program group, program, stimulation amplitude, pulsewidth, pulse rate, and/or one or more other parameters, groups orprograms to maintain therapeutic efficacy. When a patient lies down, forexample, IMD 14 may automatically reduce stimulation amplitude so thatpatient 12 does not need to reduce stimulation amplitude manually. Insome cases, IMD 14 may communicate with external programmer 20 topresent a proposed change in stimulation in response to a posture statechange, and receive approval or rejection of the change from a user,such as patient 12 or a clinician, before automatically applying thetherapy change. In some examples, posture state detection may also beused to provide notifications, such as providing notification via awireless link to a care giver that a patient has potentially experienceda fall.

Referring still to FIG. 1A, a user, such as a clinician or patient 12,may interact with a user interface of external programmer 20 to programIMD 14. The user interface may include an output device for presentationof information, and an input device to receive user input. Programmingof IMD 14 may refer generally to the generation and transfer ofcommands, programs, or other information to control the operation of IMD14. For example, external programmer 20 may transmit programs, parameteradjustments, program selections, group selections, or other informationto control the operation of IMD 14, e.g., by wireless telemetry. As oneexample, external programmer 20 may transmit parameter adjustments tosupport therapy changes due to posture changes by patient 12. As anotherexample, a user may select programs or program groups. Again, a programmay be characterized by an electrode combination, electrode polarities,voltage or current amplitude, pulse width, pulse rate, and/or duration.A group may be characterized by multiple programs that are deliveredsimultaneously or on an interleaved or rotating basis.

During the delivery of stimulation therapy, patient 12 may make patienttherapy adjustments, i.e., patient adjustments to one or more parametersof a therapy via an input device of a user interface of a programmer, tocustomize the therapy either after patient 12 moves to a differentposture state or in anticipation of the next posture state. In exampleswhere IMD 14 is in a record mode to store all patient therapyadjustments associated with a specific posture state, IMD 14 mayimplement a method to ensure that patient therapy adjustments areassociated with the correct posture state intended by patient 12 whenthe therapy adjustment was made. The patient 12 may occupy the posturestate multiple times such that there are multiple instances of thesensed posture state.

Each time the patient 12 occupies the posture state, the patient mayenter one or more therapy adjustments. Hence, the multiple therapyadjustments may be obtained over multiple instances of the sensedposture state, i.e., multiple, different times at which the patientoccupies the posture state over a time interval, and associated with theposture state. IMD 14 may use a posture search timer having a searchperiod and a posture stability timer having a stability period after anytherapy adjustment in order to match the therapy adjustment to theappropriate posture state. The therapy adjustment is associated with afinal posture state only when a final posture state began within thesearch period of the posture search timer and lasts beyond the stabilityperiod of the posture stability timer. In this manner, therapyadjustments are not associated with a posture state that does not remainconstant or is not occupied soon enough after the therapy adjustment.

In some cases, external programmer 20 may be characterized as aphysician or clinician programmer if it is primarily intended for use bya physician or clinician. In other cases, external programmer 20 may becharacterized as a patient programmer if it is primarily intended foruse by a patient, e.g., for entry of patient input to specify patientadjustments to one or more therapy parameters. A patient programmer isgenerally accessible to patient 12 and, in many cases, may be a portabledevice that may accompany the patient throughout the patient's dailyroutine. In general, a physician or clinician programmer may supportselection and generation of programs by a clinician for use bystimulator 14, whereas a patient programmer may support adjustment andselection of such programs by a patient during ordinary use, eithermanually or via other user input media.

External programmer 20 may present posture state data stored in IMD 14from the detected posture states of patient 12. The posture state datamay be acquired by external programmer 20 to generate posture stateinformation, e.g., therapy adjustment information. IMD 14 may also storeany associations between the therapy adjustments and the posture statesfor which the therapy adjustments were intended during a record mode,i.e., therapy adjustment information. By recording all therapyadjustments made for a program in each of the posture states, includingeach of the multiple instances of the sensed posture states, externalprogrammer 20 may be able to present therapy adjustment information tothe user that indicates patient 12 desired stimulation parameters basedupon parameter use. For example, the user may be able to identify themost recent stimulation parameters desired by patient 12, the minimumand maximum allowable amplitudes, or even the quantified number oftherapy adjustments to indicate that patient 12 is either satisfied witha program or cannot readily find suitable parameters for a program withmany therapy adjustments.

The therapy adjustment information stored during the record mode may bepresented in any number of different manners. For example, an outputdevice of the user interface may present each program of a group and therespective number of therapy adjustments and the range of suchamplitudes defined by the therapy adjustments. Alternatively, an outputdevice of the user interface may also, or instead, present the last(i.e., most recent) amplitude used by patient 12 to deliver therapy witheach program. In any manner, the therapy adjustment information may bepresented in a graphical, numerical, or textual mode on externalprogrammer 20. The user may be able to customize the presentation of thetherapy adjustment information in other examples.

In some examples, external programmer 20 may utilize the associations ofthe therapy adjustments to posture states in order to further minimizetime needed to program all therapy programs. When presenting theamplitude ranges of the therapy adjustments for each therapy program,the user may be able to provide a single confirmation input that setsthe amplitude for all programs to some nominal therapy parameter, forexample. The nominal therapy parameter may be a minimum amplitudeassociated with the program and posture state, the last amplitudeassociated with the program and posture state, or some other therapyparameter already stored by IMD 14 in association with each therapyprogram and posture state. The therapy parameter may be referred to asnominal in the sense that it refers to a parameter value by a name thatis descriptive of the value, rather than to a specific, absoluteparameter value. In cases where a program has not been associated withany therapy adjustment, no new stimulation parameter may be programmedto the program.

In other examples, external programmer 20 may generate a suggestedtherapy parameter based upon the therapy adjustment information and aguided algorithm. The suggested therapy parameter may be a specifictherapy parameter value that is visible to the user, but is signified asbeing suggested by the guided algorithm. The guided algorithm may be anequation, set of equations, look-up table, or other technique forgenerating a suggested therapy parameter that may define stimulationtherapy effective to patient 12. In this manner, external programmer 20analyzes the therapy adjustment information for the most appropriatestimulation parameters that fit the desires of the user. The guidedalgorithm may generate a low or high weighted average, a safe averagethat minimizes the chances of overstimulation, a trend target thatweights more recent patient adjustments to therapy greater than oldertherapy adjustments, or even an intergroup average that looks to therapyadjustments to programs in different groups that provide stimulationtherapy. In any case, the user may be able to program the plurality ofprograms with each suggested therapy parameter with the selection of asingle confirmation input.

IMD 14 may be constructed with a biocompatible housing, such as titaniumor stainless steel, or a polymeric material such as silicone orpolyurethane, and surgically implanted at a site in patient 12 near thepelvis. IMD 14 may also be implanted in patient 12 at a locationminimally noticeable to patient 12. Alternatively, IMD 14 may beexternal with percutaneously implanted leads. For SCS, IMD 14 may belocated in the lower abdomen, lower back, upper buttocks, or otherlocation to secure IMD 14. Leads 16 may be tunneled from IMD 14 throughtissue to reach the target tissue adjacent to spinal cord 18 forstimulation delivery.

At the distal tips of leads 16 are one or more electrodes (not shown)that transfer the electrical stimulation from the lead to the tissue.The electrodes may be electrode pads on a paddle lead, circular (e.g.,ring) electrodes surrounding the body of leads 16, conformableelectrodes, cuff electrodes, segmented electrodes, or any other type ofelectrodes capable of forming unipolar, bipolar or multipolar electrodeconfigurations for therapy. In general, ring electrodes arranged atdifferent axial positions at the distal ends of leads 16 will bedescribed for purposes of illustration.

FIG. 1B is a conceptual diagram illustrating an implantable stimulationsystem 22 including three implantable stimulation leads 16A, 16B, 16C(collectively leads 16). System 22 generally conforms to system 10 ofFIG. 1A, but includes a third lead along spinal cord 18. Accordingly,IMD 14 may deliver stimulation via combinations of electrodes carried byall three leads 16, or a subset of the three leads. The third lead,e.g., lead 16C, may include a greater number of electrodes than leads16A and 16B and be positioned between leads 16A and 16B or on one sideof either lead 16A or 16B. External programmer 20 may be initially toldthe number and configuration of leads 16 in order to appropriatelyprogram stimulation therapy.

For example, leads 16A and 16B could include four electrodes, while lead16C includes eight or sixteen electrodes, thereby forming a so-called4-8-4 or 4-16-4 lead configuration. Other lead configurations, such as8-16-8, 8-4-8, 16-8-16, 16-4-16, are possible. In some cases, electrodeson lead 16C may be smaller in size and/or closer together than theelectrodes of leads 16A or 16B. Movement of lead 16C due to changingactivities or postures of patient 12 may, in some instances, moreseverely affect stimulation efficacy than movement of leads 16A or 16B.Patient 12 may further benefit from the ability of IMD 14 to detectposture states and associated changes and automatically adjuststimulation therapy to maintain therapy efficacy in a three lead system22.

FIG. 1C is a conceptual diagram illustrating an implantable drugdelivery system 24 including one delivery catheter 28 coupled to IMD 26.As shown in the example of FIG. 1C, drug delivery system 24 issubstantially similar to systems 10 and 22. However, drug deliverysystem 24 performs the similar therapy functions via delivery of drugstimulation therapy instead of electrical stimulation therapy. IMD 26functions as a drug pump in the example of FIG. 1C, and IMD 26communicates with external programmer 20 to initialize therapy or modifytherapy during operation. In addition, IMD 26 may be refillable to allowchronic drug delivery.

Although IMD 26 is shown as coupled to only one catheter 28 positionedalong spinal cord 18, additional catheters may also be coupled to IMD26. Multiple catheters may deliver drugs or other therapeutic agents tothe same anatomical location or the same tissue or organ. Alternatively,each catheter may deliver therapy to different tissues within patient 12for the purpose of treating multiple symptoms or conditions. In someembodiments, IMD 26 may be an external device which includes apercutaneous catheter that forms catheter 28 or that is coupled tocatheter 28, e.g., via a fluid coupler. In other embodiments, IMD 26 mayinclude both electrical stimulation as described in IMD 14 and drugdelivery therapy.

IMD 26 may also operate using parameters that define the method of drugdelivery. IMD 26 may include programs, or groups of programs, thatdefine different delivery methods for patient 12. For example, a programthat controls delivery of a drug or other therapeutic agent may includea titration rate or information controlling the timing of bolusdeliveries. Patient 12 may use external programmer 20 to adjust theprograms or groups of programs to regulate the therapy delivery.

Similar to IMD 14, IMD 26 may include a posture state module thatmonitors the patient 12 posture state and adjusts therapy accordingly.For example, the posture state module may indicate that patient 12transitions from lying down to standing up. IMD 26 may automaticallyincrease the rate of drug delivered to patient 12 in the standingposition if patient 12 has indicated that pain increased when standing.This automated adjustment to therapy based upon posture state may beactivated for all or only a portion of the programs used by IMD 26 todeliver therapy.

FIG. 2 is a conceptual diagram illustrating an example patientprogrammer 30 for programming stimulation therapy delivered by animplantable medical device. Patient programmer 30 is an exampleembodiment of external programmer 20 illustrated in FIGS. 1A, 1B and 1Cand may be used with either IMD 14 or IMD 26. In alternativeembodiments, patient programmer 30 may be used with an external medicaldevice. As shown in FIG. 2, patient programmer 30 provides a userinterface (not shown) for a user, such as patient 12, to manage andprogram stimulation therapy. Patient programmer 30 is protected byhousing 32, which encloses circuitry necessary for patient programmer 30to operate.

Patient programmer 30 also includes display 36, which may form part ofan output device of a user interface, power button 38, increase button52, decrease button 50, sync button 58, stimulation ON button 54, andstimulation OFF button 56. Cover 34 protects display 36 from beingdamaged during use of patient programmer 30. Patient programmer 30 alsoincludes control pad 40 which forms part of an input device of a userinterface and allows a user to navigate through items displayed ondisplay 36 in the direction of arrows 42, 44, 46, and 48. In someembodiments, the buttons and pad 40 may take the form of soft keys(e.g., with functions and contexts indicated on display 36), withfunctionality that may change, for example, based on current programmingoperation or user preference. In alternative embodiments, display 36 maybe a touch screen in which patient 12 may interact directly with display36 without the use of control pad 40 or even increase button 52 anddecrease button 50.

In the illustrated embodiment, patient programmer 30 is a hand helddevice. Patient programmer 30 may accompany patient 12 throughout adaily routine. In some cases, patient programmer 30 may be used by aclinician when patient 12 visits the clinician in a hospital or clinic.In other embodiments, patient programmer 30 may be a clinicianprogrammer that remains with the clinician or in the clinic and is usedby the clinician and/or patient 12 when the patient is in the clinic. Inthe case of a clinician programmer, small size and portability may beless important. Accordingly, a clinician programmer may be sized largerthan a patient programmer, and it may provide a larger screen for morefull-featured programming.

Housing 32 may be constructed of a polymer, metal alloy, composite, orcombination material suitable to protect and contain components ofpatient programmer 30. In addition, housing 32 may be partially orcompletely sealed such that fluids, gases, or other elements may notpenetrate the housing and affect components therein. Power button 38 mayturn patient programmer 30 ON or OFF as desired by patient 12. Patient12 may control the illumination level, or backlight level, of display 36by using control pad 40 to navigate through the user interface andincrease or decrease the illumination level with decrease and increasebuttons 50 and 52. In some embodiments, illumination may be controlledby a knob that rotates clockwise and counter-clockwise to controlpatient programmer 30 operational status and display 36 illumination.Patient programmer 30 may be prevented from turning OFF during telemetrywith IMD 14 or another device to prevent the loss of transmitted data orthe stalling of normal operation. Alternatively, patient programmer 30and IMD 14 may include instructions that handle possible unplannedtelemetry interruption, such as battery failure or inadvertent deviceshutdown.

Display 36 may be a liquid crystal display (LCD), dot matrix display,organic light-emitting diode (OLED) display, touch screen, or similarmonochrome or color display capable of providing visible information topatient 12. Display 36 may provide a user interface regarding currentstimulation therapy, posture state information, provide a user interfacefor receiving feedback or medication input from patient 12, display anactive group of stimulation programs, and display operational status ofpatient programmer 30 or IMDs 14 or 26. For example, patient programmer30 may provide a scrollable list of groups, and a scrollable list ofprograms within each group, via display 36.

Display 36 may present a visible posture state indication. In addition,display 36 may present therapy adjustment information stored during therecord mode of IMD 14 and even present nominal or suggested therapyparameters for a plurality of programs. Patient 12 may then selectivelyset the plurality of programs to the respective nominal or suggestedtherapy parameters via a single confirmation input. As described herein,patient programmer 30 may be configured to perform any tasks describedwith respect to clinician programmer 60 (described below in reference toFIG. 3) or another external programmer 20.

Control pad 40 allows patient 12 to navigate through items displayed ondisplay 36. Patient 12 may press control pad 40 on any of arrows 42, 44,46, and 48 in order to move to another item on display 36 or move toanother screen not currently shown on the display. In some embodiments,pressing the middle of control pad 40 may select any item highlighted indisplay 36. In other embodiments, scroll bars, a scroll wheel,individual buttons, or a joystick may perform the complete or partialfunctions of control pad 40. In alternative embodiments, control pad 40may be a touch pad that allows patient 12 to move a cursor within theuser interface displayed on display 36 to manage therapy or reviewposture state information.

Decrease button 50 and increase button 52 provide an input mechanism forpatient 12. In general, decrease button 50 may decrease the value of ahighlighted stimulation parameter every time the decrease button ispressed. In contrast, increase button 52 may increase the value of ahighlighted stimulation parameter one step every time the increasebutton is pressed. While buttons 50 and 52 may be used to control thevalue of any stimulation parameter, buttons 50 and 52 may also controlpatient feedback input. When either of buttons 50 and 52 is selected,patient programmer 30 may initialize communication with IMD 14 or 26 tochange therapy accordingly.

When depressed by patient 12, stimulation ON button 54 directsprogrammer 30 to generate a command for communication to IMD 14 thatturns on stimulation therapy. Stimulation OFF button 56 turns offstimulation therapy when depressed by patient 12. Sync button 58 forcespatient programmer 30 to communicate with IMD 14. When patient 12 entersan automatic posture response screen of the user interface, pressingsync button 58 turns on the automatic posture response to allow IMD 14to automatically change therapy according to the posture state ofpatient 12. Pressing sync button 58 again, when the automatic postureresponse screen is displayed, turns off the automatic posture response.In the example of FIG. 2, patient 12 may use control pad 40 to adjustthe volume, contrast, illumination, time, and measurement units ofpatient programmer 30.

In some embodiments, buttons 54 and 56 may be configured to performoperational functions related to stimulation therapy or the use ofpatient programmer 30. For example, buttons 54 and 56 may control thevolume of audible sounds produced by programmer 20, wherein button 54increases the volume and button 56 decreases the volume. Button 58 maybe pressed to enter an operational menu that allows patient 12 toconfigure the user interface of patient programmer 30 to the desires ofpatient 12. For example, patient 12 may be able to select a language,backlight delay time, display 36 brightness and contrast, or othersimilar options. In alternative embodiments, buttons 50 and 52 maycontrol all operational and selection functions, such as those relatedto audio volume or stimulation therapy.

Patient programmer 30 may take other shapes or sizes not describedherein. For example, patient programmer 30 may take the form of aclam-shell shape, similar to some cellular phone designs. When patientprogrammer 30 is closed, some or all elements of the user interface maybe protected within the programmer. When patient programmer 30 isopened, one side of the programmer may contain a display while the otherside may contain input mechanisms. In any shape, patient programmer 30may be capable of performing the requirements described herein.Alternative embodiments of patient programmer 30 may include other inputmechanisms such as a keypad, microphone, camera lens, or any other mediainput that allows the user to interact with the user interface providedby patient programmer 30.

In alternative embodiments, the buttons of patient programmer 30 mayperform different functions than the functions provided in FIG. 2 as anexample. In addition, other embodiments of patient programmer 30 mayinclude different button layouts or different numbers of buttons. Forexample, patient programmer 30 may even include a single touch screenthat incorporates all user interface functionality with a limited set ofbuttons or no other buttons.

FIG. 3 is a conceptual diagram illustrating an example clinicianprogrammer 60 for programming stimulation therapy delivered by animplantable medical device. Clinician programmer 60 is an exampleembodiment of external programmer 20 illustrated in FIGS. 1A, 1B and 1Cand may be used with either IMD 14 or IMD 26. In alternativeembodiments, clinician programmer 60 may be used with an externalmedical device. As shown in FIG. 3, clinician programmer 60 provides auser interface (not shown) for a user, such as a clinician, physician,technician, or nurse, to manage and program stimulation therapy. Inaddition, clinician programmer 60 may be used to review objectiveposture state information to monitor the progress and therapy efficacyof patient 12. Clinician programmer 60 is protected by housing 62, whichencloses circuitry necessary for clinician programmer 60 to operate.

Clinician programmer 60 is used by the clinician or other user to modifyand review therapy to patient 12. The clinician may define each therapyparameter value for each of the programs that define stimulationtherapy. The therapy parameters, such as amplitude, may be definedspecifically for each of the posture states that patient 12 will beengaged in during therapy. In addition, the clinician may use clinicianprogrammer 60 to define each posture state of patient 12 by using theposture cones described herein or some other technique for associatingposture state sensor output to the posture state of patient 12.

Clinician programmer 60 includes display 64 and power button 66. In theexample of FIG. 3, display 64 is a touch screen that accepts user inputvia touching certain areas within display 64. The user may use stylus 68to touch display 64 and select virtual buttons, sliders, keypads, dials,or other such representations presented by the user interface shown bydisplay 64. In some embodiments, the user may be able to touch display64 with a finger, pen, or any other pointing device. In alternativeembodiments, clinician programmer 60 may include one or more buttons,keypads, control pads, touch pads, or other devices that accept userinput, similar to patient programmer 30.

In the illustrated embodiment, clinician programmer 60 is a hand helddevice. Clinician programmer 60 may be used within the clinic or onin-house patient calls. Clinician programmer 60 may be used tocommunicate with multiple IMDs 14 and 26 within different patients. Inthis manner, clinician programmer 60 may be capable of communicatingwith many different devices and retain patient data separate for otherpatient data. In some embodiments, clinician programmer 60 may be alarger device that may be less portable, such as a notebook computer,workstation, or event a remote computer that communicates with IMD 14 or26 via a remote telemetry device.

Most, if not all, of clinician programmer 60 functions may be completedvia the touch screen of display 64. The user may program stimulationtherapy, modify programs or groups, retrieve stored therapy data,retrieve posture state information, define posture states and otheractivity information, change the contrast and backlighting of display64, or any other therapy related function. In addition, clinicianprogrammer 60 may be capable of communicating with a networked server inorder to send or receive an email or other message, retrieve programminginstructions, access a help guide, send an error message, or perform anyother function that may be beneficial to prompt therapy.

Clinician programmer 60 may also allow the clinician to view historicaltherapy adjustment information stored in IMD 14 during therapy. Asmentioned previously, the therapy adjustment information includes anyassociations created between therapy parameter value adjustments andposture states for each program that delivers automatic postureresponsive stimulation. The clinician may initially orient IMD 14 topatient 12 and enable the record mode for IMD 14 to store anyassociations as therapy adjustment information. Clinician programmer 60may then acquire the therapy adjustment information from IMD 14 andpresent the information to the clinician in order to allow continuedeffective therapy modifications.

In some examples, clinician programmer 60 may also allow the clinicianto adjust the search period of the posture search timer and thestability period of the posture stability timer. The posture searchtimer and the posture stability timer enable IMD 14 to determine theposture state with which a therapy adjustment should be associated.Depending upon the condition of patient 12 or the clinician preferences,the clinician may desire to adjust the search period and stabilityperiod to most accurately reflect the intentions of patient 12. Forexample, if patient 12 has a habit of adjusting therapy long beforemaking a change to the posture state or patient 12 takes a long time toassume a desired posture state, the clinician may desire to increase thesearch period and stability period in order to properly associate thetherapy adjustment with the intended posture state. In some examples,clinician programmer 60 may suggest appropriate search periods andstability periods for patients diagnosed with particular conditions thatmay hinder their movement or involve multiple oscillations in posturestate before settling on the final posture state.

In addition, clinician programmer 60 may present nominal and suggestedtherapy parameters to the clinician based upon the stored therapyadjustment information in IMD 14. In one example, clinician programmer60 may simply present an amplitude range determined by the therapyadjustments for each program and posture state. The clinician may thenset the amplitude of each program to a nominal therapy parameterpresented on display 64 of clinician programmer 60. For example, thenominal therapy parameter may be the minimum amplitude used by patient12 for each program. Alternatively, clinician programmer 60 may presentthe last therapy adjustment for each program and posture state, or anaverage therapy adjustment. Clinician programmer 60 may then set thetherapy parameter for all displayed programs with a single confirmationinput from the clinician. This single input may decrease clinicianprogramming time and overall programming complexity.

Further, clinician programmer 60 may present a suggested therapyparameter to the clinician for each program and posture state that isbased upon the therapy adjustment information. The suggested therapyparameter may or may not be a parameter that was used from a therapyadjustment. Clinician programmer 60 may utilize a guided algorithm thatattempts to generate a suggested therapy parameter that the cliniciandesires to free the clinician from manually determining the best therapyparameter for each program. Clinician programmer 60 may utilize onealgorithm or receive a guided algorithm input from the clinician thatcustomizes how clinician programmer 60 generates the suggested therapyparameters. For example, clinician programmer 60 may use a target trendguided algorithm that weights more recent therapy adjustments so thatthe suggested therapy parameters are more representative of recentpatient 12 response to stimulation therapy.

In some cases, all processing may be performed in IMD 14 and distributedto clinician programmer 60 only for presentation to the clinician.Alternatively, IMD 14, clinician programmer 60, patient programmer 30,or another computing device may share in the processing duties oftherapy adjustment information and any other data prior to presentingthe information on clinician programmer 60. In other embodiments, IMD 14may simply transfer raw data to an external programmer 20 or othercomputing device for data processing necessary to perform the tasksdescribed herein. Accordingly, methods described in this disclosure maybe implemented within IMD 14, programmer 30, programmer 60, or within acombination of such components.

Housing 62 may be constructed of a polymer, metal alloy, composite, orcombination material suitable to protect and contain components ofclinician programmer 60. In addition, housing 62 may be partially orcompletely sealed such that fluids, gases, or other elements may notpenetrate the housing and affect components therein. Power button 66 mayturn clinician programmer 60 ON or OFF as desired by the user. Clinicianprogrammer 60 may require a password, biometric input, or other securitymeasure to be entered and accepted before the user can use clinicianprogrammer 60.

Clinician programmer 60 may take other shapes or sizes not describedherein. For example, clinician programmer 60 may take the form of aclam-shell shape, similar to some cellular phone designs. When clinicianprogrammer 60 is closed, at least a portion of display 64 is protectedwithin housing 62. When clinician programmer 60 is opened, one side ofthe programmer may contain a display while the other side may containinput mechanisms. In any shape, clinician programmer 60 may be capableof performing the requirements described herein.

FIG. 4 is a functional block diagram illustrating various components ofan IMD 14. In the example of FIG. 4, IMD 14 includes a processor 80,memory 82, stimulation generator 84, posture state module 86, telemetrycircuit 88, and power source 90. The stimulation generator 84 forms atherapy delivery module. Memory 82 may store instructions for executionby processor 80, stimulation therapy data, posture state information,posture state indications, and any other information regarding therapyor patient 12. Therapy information may be recorded for long-term storageand retrieval by a user, and the therapy information may include anydata created by or stored in IMD 14. Memory 82 may include separatememories for storing instructions, posture state information, therapyadjustment information, program histories, and any other data that maybenefit from separate physical memory modules.

Processor 80 controls stimulation generator 84 to deliver electricalstimulation via electrode combinations formed by electrodes in one ormore electrode arrays. For example, stimulation generator 84 may deliverelectrical stimulation therapy via electrodes on one or more leads 16,e.g., as stimulation pulses or continuous waveforms. Componentsdescribed as processors within IMD 14, external programmer 20 or anyother device described in this disclosure may each comprise one or moreprocessors, such as one or more microprocessors, digital signalprocessors (DSPs), application specific integrated circuits (ASICs),field programmable gate arrays (FPGAs), programmable logic circuitry, orthe like, either alone or in any suitable combination.

Stimulation generator 84 may include stimulation generation circuitry togenerate stimulation pulses or waveforms and switching circuitry toswitch the stimulation across different electrode combinations, e.g., inresponse to control by processor 80. In particular, processor 80 maycontrol the switching circuitry on a selective basis to causestimulation generator 84 to deliver electrical stimulation to selectedelectrode combinations and to shift the electrical stimulation todifferent electrode combinations in a first direction or a seconddirection when the therapy must be delivered to a different locationwithin patient 12. In other embodiments, stimulation generator 84 mayinclude multiple current sources to drive more than one electrodecombination at one time. In this case, stimulation generator 84 maydecrease current to the first electrode combination and simultaneouslyincrease current to the second electrode combination to shift thestimulation therapy.

An electrode configuration, e.g., electrode combination and associatedelectrode polarities, may be represented by a data stored in a memorylocation, e.g., in memory 82, of IMD 14. Processor 80 may access thememory location to determine the electrode combination and controlstimulation generator 84 to deliver electrical stimulation via theindicated electrode combination. To adjust electrode combinations,amplitudes, pulse rates, or pulse widths, processor 80 may commandstimulation generator 84 to make the appropriate changes to therapyaccording to instructions within memory 82 and rewrite the memorylocation to indicate the changed therapy. In other embodiments, ratherthan rewriting a single memory location, processor 80 may make use oftwo or more memory locations.

When activating stimulation, processor 80 may access not only the memorylocation specifying the electrode combination but also other memorylocations specifying various stimulation parameters such as voltage orcurrent amplitude, pulse width and pulse rate. Stimulation generator 84,e.g., under control of processor 80, then makes use of the electrodecombination and parameters in formulating and delivering the electricalstimulation to patient 12.

According to examples described herein, such stimulation parameters maybe adjusted to modify stimulation therapy delivered by IMD 14 based onthe detected posture state of patient 12. In some examples, processor 80may detect a posture state of patient 12 via posture state module 86that indicates that a modification of the stimulation therapy isappropriate, e.g., according to instructions stored in memory 82.Processor 80 may access instructions for modifying the stimulationtherapy based on the patient 12 posture state, e.g., by changing from astimulation program appropriate for the previous posture state to astimulation program appropriate for patient's current posture state.

An exemplary range of electrical stimulation parameters likely to beeffective in treating chronic pain, e.g., when applied to spinal cord18, are listed below. While stimulation pulses are described,stimulation signals may be of any of a variety of forms such as sinewaves or the like.

Pulse Rate: between approximately 0.5 Hz and 1200 Hz, more preferablybetween approximately 5 Hz and 250 Hz, and still more preferably betweenapproximately 30 Hz and 130 Hz.

Amplitude: between approximately 0.1 volts and 50 volts, more preferablybetween approximately 0.5 volts and 20 volts, and still more preferablybetween approximately 1 volt and 10 volts. In other embodiments, acurrent amplitude may be defined as the biological load in the voltagethat is delivered. For example, the range of current amplitude may bebetween approximately 0.1 milliamps (mA) and 50 mA.

Pulse Width: between about 10 microseconds and 5000 microseconds, morepreferably between approximately 100 microseconds and 1000 microseconds,and still more preferably between approximately 180 microseconds and 450microseconds.

In other applications, different ranges of parameter values may be used.For deep brain stimulation (DBS), as one example, alleviation orreduction of symptoms associated with Parkinson's disease, essentialtremor, epilepsy or other disorders may make use of stimulation having apulse rate in the range of approximately 0.5 to 1200 Hz, more preferably5 to 250 Hz, and still more preferably 30 to 185 Hz, and a pulse widthin the range of approximately 10 microseconds and 5000 microseconds,more preferably between approximately 60 microseconds and 1000microseconds, still more preferably between approximately 60microseconds and 450 microseconds, and even more preferably betweenapproximately 60 microseconds and 150 microseconds. Amplitude rangessuch as those described above with reference to SCS, or other amplituderanges, may be used for different DBS applications.

Processor 80 accesses stimulation parameters in memory 82, e.g., asprograms and groups of programs. Upon selection of a particular programgroup, processor 80 may control stimulation generator 84 to deliverstimulation according to the programs in the groups, e.g.,simultaneously or on a time-interleaved basis. A group may include asingle program or multiple programs. As mentioned previously, eachprogram may specify a set of stimulation parameters, such as amplitude,pulse width and pulse rate. In addition, each program may specify aparticular electrode combination for delivery of stimulation. Again, theelectrode combination may specify particular electrodes in a singlearray or multiple arrays, e.g., on a single lead or among multipleleads. Processor 80 also may control telemetry circuit 88 to send andreceive information to and from external programmer 20. For example,telemetry circuit 88 may send information to and receive informationfrom patient programmer 30.

Posture state module 86 allows IMD 14 to sense the patient posturestate, e.g., posture, activity or any other static position or motion ofpatient 12. In the example of FIG. 4, posture state module 86 mayinclude one or more posture state sensors, e.g., one or moreaccelerometers such as three-axis accelerometers, capable of detectingstatic orientation or vectors in three-dimensions. Exampleaccelerometers may include micro-electro-mechanical accelerometers. Inother examples, posture state module 86 may alternatively oradditionally include one or more gyroscopes, pressure transducers orother sensors to sense the posture state of patient 12. Posture stateinformation generated by posture state module 86 and processor 80 maycorrespond to an activity, posture, or posture and activity undertakenby patient 12 or a gross level of physical activity, e.g., activitycounts based on footfalls or the like.

Posture state information from posture state module 86 may be stored inmemory 82 to be later reviewed by a clinician, used to adjust therapy,presented as a posture state indication to patient 12, or somecombination thereof. As an example, processor 80 may record the posturestate parameter value, or output, of the 3-axis accelerometer and assignthe posture state parameter value to a certain predefined postureindicated by the posture state parameter value. In this manner, IMD 14may be able to track how often patient 12 remains within a certainposture defined within memory 82. IMD 14 may also store which group orprogram was being used to deliver therapy when patient 12 was in thesensed posture. Further, processor 80 may also adjust therapy for a newposture when posture state module 86 indicates that patient 12 has infact changed postures. Therefore, IMD 14 may be configured to provideposture state-responsive stimulation therapy to patient 12. Stimulationadjustments in response to posture state may be automatic orsemi-automatic (subject to patient approval). In many cases, fullyautomatic adjustments may be desirable so that IMD 14 may react morequickly to posture state changes.

As described herein, the posture state data, or raw data of the posturestate information, is stored by system 10 to be used at a later time.The posture state information may also be used in addition to thetherapy adjustment information when the user desires to view moredetailed information related to the posture states engaged by patient12. Memory 82 may store all of the posture state data detected duringtherapy or use of IMD 14, or memory 82 may periodically offload theposture state data to clinician programmer 60 or a different externalprogrammer 20 or device. In other examples, memory 82 may reserve aportion of the memory to store recent posture state data easilyaccessible to processor 80 for analysis. In addition, older posturestate data may be compressed within memory 82 to require less memorystorage until later needed by external programmer 20 or processor 80.

A posture state parameter value from posture state module 86 thatindicates the posture state of patient 12 may constantly vary throughoutthe daily activities of patient 12. However, a certain activity (e.g.,walking, running, or biking) or a posture (e.g., standing, sitting, orlying down) may include multiple posture state parameter values fromposture state module 86. In this manner, a posture state may include abroad range of posture state parameter values. Memory 82 may includedefinitions for each posture state of patient 12. In one example, thedefinitions of each posture state may be illustrated as a cone inthree-dimensional space. Whenever the posture state parameter value,e.g., a sensed coordinate vector, from the three-axis accelerometer ofposture state module 86 resides within a predefined cone, processor 80indicates that patient 12 is in the posture state of the cone. In otherexamples, posture state parameter value from the 3-axis accelerometermay be compared to a look-up table or equation to determine the posturestate in which patient 12 currently resides.

Posture state-responsive stimulation may allow IMD 14 to implement acertain level of automation in therapy adjustments. Automaticallyadjusting stimulation may free patient 12 from the constant task ofmanually adjusting therapy parameters each time patient 12 changesposture or starts and stops a certain posture state. Such manualadjustment of stimulation parameters can be tedious, requiring patient12 to, for example, depress one or more keys of patient programmer 30multiple times during the patient posture state to maintain adequatesymptom control. Alternatively, patient 12 may be unable to manuallyadjust the therapy if patient programmer 30 is unavailable or patient 12is preoccupied. In some embodiments, patient 12 may eventually be ableto enjoy posture state responsive stimulation therapy without the needto continue making changes for different postures via patient programmer30. Instead, patient 12 may transition immediately or over time to fullyautomatic adjustments based on posture state.

Although posture state module 86 is described as containing the 3-axisaccelerometer, posture state module 86 may contain multiple single-axisaccelerometers, dual-axis accelerometers, 3-axis accelerometers, or somecombination thereof. In some examples, an accelerometer or other sensormay be located within or on IMD 14, on one of leads 16 (e.g., at thedistal tip or at an intermediate position), an additional sensor leadpositioned somewhere within patient 12, within an independentimplantable sensor, or even worn on patient 12. For example, one or moremicrosensors may be implanted within patient 12 to communicate posturestate information wirelessly to IMD 14. In this manner, the patient 12posture state may be determined from multiple posture state sensorsplaced at various locations on or within the body of patient 12.

In other embodiments, posture state module 86 may additionally oralternatively be configured to sense one or more physiologicalparameters of patient 12. For example, physiological parameters mayinclude heart rate, electromyography (EMG), an electroencephalogram(EEG), an electrocardiogram (ECG), temperature, respiration rate, or pH.These physiological parameters may be used by processor 80, in someembodiments, to confirm or reject changes in sensed posture state thatmay result from vibration, patient travel (e.g., in an aircraft, car ortrain), or some other false positive of posture state.

In some embodiments, processor 80 processes the analog output of theposture state sensor in posture state module 86 to determine activityand/or posture data. For example, where the posture state sensorcomprises an accelerometer, processor 80 or a processor of posture statemodule 86 may process the raw signals provided by the posture statesensor to determine activity counts. In some embodiments, processor 80may process the signals provided by the posture state sensor todetermine velocity of motion information along each axis.

In one example, each of the x, y, and z signals provided by the posturestate sensor has both a DC component and an AC component. The DCcomponents describes the gravitational force exerted upon the sensor andcan thereby be used to determine orientation of the sensor within thegravitational field of the earth. Assuming the orientation of the sensoris relatively fixed with respect to the patient, the DC components ofthe x, y and z signals may be utilized to determine the patient'sorientation within the gravitational field, and hence to determine theposture of the patient.

The AC component of the x, y and z signals yields information aboutpatient motion. In particular, the AC component of a signal may be usedto derive a value for an activity describing the patient's motion, oractivity. This activity may involve a level, direction of motion, oracceleration of the patient.

One method for determining the activity is an activity count. Anactivity count may be used to indicate the activity or activity level ofpatient 12. For example, a signal processor may sum the magnitudes ofthe AC portion of an accelerometer signal for N consecutive samples. Forinstance, assuming sampling occurs as 25 Hz, N may be set to 25, so thatcount logic provides the sum of the samples that are obtained in onesecond. This sum may be referred to as an “activity count.” The number“N” of consecutive samples may be selected by the processor based on thecurrent posture state, if desired. The activity count may be theactivity portion of the activity parameter value that is added to theposture portion. The resulting activity parameter value may thenincorporate both activity and posture to generate an accurate indicationof the motion of patient 12.

As another example, the activity parameter value may be defineddescribing direction of motion. This activity parameter value may beassociated with a vector and an associated tolerance, which may be adistance from the vector. Another example of an activity parameter valuerelates to acceleration. The value quantifying a level of change ofmotion over time in a particular direction may be associated with thisparameter referenced in the activity parameter value.

Processor 80 may monitor the posture state of patient 12 and associateany therapy adjustments that patient 12 makes to the posture statecurrently occupied by patient 12. However, processor 80 may also employtechniques that allow a therapy adjustment to be associated with a laterposture state in cases when patient 12 makes a therapy adjustment inanticipation of changing the posture state. Patient 12 may desire tomake this preemptory adjustment to avoid being over-stimulated orunder-stimulated when the patient assumes the new posture state.

Processor 80 may employ multiple timers that monitor therapy adjustmentsand when a new posture state occurs, as a result of a posture statetransition. Processor 80 may use a posture search timer having a searchperiod, where the search timer begins upon the detection of the therapyadjustment and expires when the search period lapses. The posture searchtimer allows a certain amount of time, or the search period, for patient12 to finally engage in the intended posture state. In addition,processor 80 uses a posture stability timer, where the posture stabilitytimer begins upon the sensing of a different posture state and requiresa certain amount of time, the stability period, to elapse while patient12 is in the same posture state before the posture state can beconsidered the final posture state. A therapy adjustment is onlyassociated with a posture state when the final posture state is started,i.e., the stability timer is started, prior to the expiration of thesearch period and the final posture state lasts at least as long as thestability period. Any other therapy adjustments are either associatedwith the initial posture state patient 12 was engaged in when thetherapy was adjusted or not associated with any posture state, dependingupon the instructions stored in memory 82.

Although external programmer 20 may perform any processing on thetherapy adjustment information, such as the association of therapyadjustments to posture states, processor 80 of IMD 14 may be configuredto analyze the information and generate desired information. Forexample, processor 80 may generate nominal therapy parameters orsuggested therapy parameters based upon the therapy adjustmentinformation stored in memory 82. In this manner, IMD 14 may transmit thenominal or suggested therapy parameters directly to external programmer20 for presentation to the user. Any other shared processing between IMD14 and external programmer 20 is also contemplated.

Wireless telemetry in IMD 14 with external programmer 20, e.g., patientprogrammer 30 or clinician programmer 60, or another device may beaccomplished by radio frequency (RF) communication or proximal inductiveinteraction of IMD 14 with external programmer 20. Telemetry circuit 88may send information to and receive information from external programmer20 on a continuous basis, at periodic intervals, at non-periodicintervals, or upon request from the stimulator or programmer. To supportRF communication, telemetry circuit 88 may include appropriateelectronic components, such as amplifiers, filters, mixers, encoders,decoders, and the like.

Power source 90 delivers operating power to the components of IMD 14.Power source 90 may include a small rechargeable or non-rechargeablebattery and a power generation circuit to produce the operating power.Recharging may be accomplished through proximal inductive interactionbetween an external charger and an inductive charging coil within IMD14. In some embodiments, power requirements may be small enough to allowIMD 14 to utilize patient motion and implement a kineticenergy-scavenging device to trickle charge a rechargeable battery. Inother embodiments, traditional batteries may be used for a limitedperiod of time. As a further alternative, an external inductive powersupply could transcutaneously power IMD 14 when needed or desired.

FIG. 5 is a functional block diagram illustrating various components ofan IMD 26 that is a drug pump. IMD 26 is a drug pump that operatessubstantially similar to IMD 14 of FIG. 4. IMD 26 includes processor 92,memory 94, pump module 96, posture state module 98, telemetry circuit100, and power source 102. Instead of stimulation generator 84 of IMD14, IMD 26 includes pump module 96 for delivering drugs or some othertherapeutic agent via catheter 28. Pump module 96 may include areservoir to hold the drug and a pump mechanism to force drug out ofcatheter 28 and into patient 12.

Processor 92 may control pump module 96 according to therapyinstructions stored within memory 94. For example, memory 94 may containthe programs or groups of programs that define the drug delivery therapyfor patient 12. A program may indicate the bolus size or flow rate ofthe drug, and processor 92 may accordingly deliver therapy. Processor 92may also use posture state information from posture state module 98 toadjust drug delivery therapy when patient 12 changes posture states,e.g., adjusts his or her posture. In alternative embodiments, system 10may be employed by an implantable medical device that delivers therapyvia both electrical stimulation therapy and drug delivery therapy as acombination of IMD 14 and IMD 26.

FIG. 6 is a functional block diagram illustrating various components ofan external programmer 20 for IMDs 14 or 26. As shown in FIG. 6,external programmer 20 includes processor 104, memory 108, telemetrycircuit 110, user interface 106, and power source 112. Externalprogrammer 20 may be embodied as patient programmer 30 or clinicianprogrammer 60. A clinician or patient 12 interacts with user interface106 in order to manually change the stimulation parameters of a program,change programs within a group, turn posture responsive stimulation ONor OFF, view therapy information, view posture state information, orotherwise communicate with IMDs 14 or 26.

User interface 106 may include a screen and one or more input buttons,as in the example of patient programmer 30, that allow externalprogrammer 20 to receive input from a user. Alternatively, userinterface 106 may additionally or only utilize a touch screen display,as in the example of clinician programmer 60. The screen may be a liquidcrystal display (LCD), dot matrix display, organic light-emitting diode(OLED) display, touch screen, or any other device capable of deliveringand/or accepting information. For visible posture state indications, adisplay screen may suffice. For audible and/or tactile posture stateindications, programmer 20 may further include one or more audiospeakers, voice synthesizer chips, piezoelectric buzzers, or the like.

Input buttons for user interface 106 may include a touch pad, increaseand decrease buttons, emergency shut off button, and other buttonsneeded to control the stimulation therapy, as described above withregard to patient programmer 30. Processor 104 controls user interface106, retrieves data from memory 108 and stores data within memory 108.Processor 104 also controls the transmission of data through telemetrycircuit 110 to IMDs 14 or 26. Memory 108 includes operation instructionsfor processor 104 and data related to patient 12 therapy.

User interface 106 is configured to present therapy adjustmentinformation to the user for monitoring adjustments made by patient 12and allowing single input and guided programming options for the user.After IMD 14 has associated therapy adjustments to posture states, userinterface 106 of external programmer 20 may present the associations tothe user as a range of therapy adjustments, maximum and minimum valuesof the adjusted parameters, last adjustments made, number of adjustmentsmade for each program and posture state, or any other details of theassociations. The number of patient therapy adjustments may be recordedbased on the cumulative number of adjustments made by the patient 12over the course of a therapy session when the patient may occupy each ofthe posture states multiple times. In particular, the number ofadjustments may be a cumulative number of adjustments over multipleinstances of the sensed posture state, i.e., multiple times in which thepatient occupied the posture state. In addition, user interface 106 maydisplay the therapy adjustment information as graphical bar graphs orcharts, numerical spread sheets, or any other manner in whichinformation may be displayed. Further, user interface 106 may presentnominal or suggested therapy parameters that the user may accept for allprograms by making one confirmation input to user interface 106.

The therapy adjustment information may also be stored within memory 108periodically during therapy, whenever external programmer 20communicates within IMD 14, or only when the user desired to use thetherapy adjustment information. Memory 108 may include a separate memoryfor therapy adjustment information as opposed to other posture stateinformation or operational instructions. In addition, if memory 108 doesstore posture state information from patient 12, memory 108 may use oneor more hardware or software security measures to protect the identifyof patient 12. For example, memory 108 may have separate physicalmemories for each patient or the user may be required to enter apassword to access each patient's posture state data.

Telemetry circuit 110 allows the transfer of data to and from IMD 14, orIMD 26. Telemetry circuit 110 may communicate automatically with IMD 14at a scheduled time or when the telemetry circuit detects the proximityof the stimulator. Alternatively, telemetry circuit 110 may communicatewith IMD 14 when signaled by a user through user interface 106. Tosupport RF communication, telemetry circuit 110 may include appropriateelectronic components, such as amplifiers, filters, mixers, encoders,decoders, and the like. Power source 112 may be a rechargeable battery,such as a lithium ion or nickel metal hydride battery. Otherrechargeable or conventional batteries may also be used. In some cases,external programmer 20 may be used when coupled to an alternatingcurrent (AC) outlet, i.e., AC line power, either directly or via anAC/DC adapter.

In some examples, external programmer 20 may be configured to rechargeIMD 14 in addition to programming IMD 14. Alternatively, a rechargingdevice may be capable of communication with IMD 14. Then, the rechargingdevice may be able to transfer programming information, data, or anyother information described herein to IMD 14. In this manner, therecharging device may be able to act as an intermediary communicationdevice between external programmer 20 and IMD 14. The techniquesdescribed herein may be communicated between IMD 14 via any type ofexternal device capable of communication with IMD 14.

FIG. 7 is a block diagram illustrating an example system 120 thatincludes an external device, such as a server 122, and one or morecomputing devices 124A-124N, that are coupled to IMD 14 and externalprogrammer 20 shown in FIGS. 1A-1C via a network 126. In this example,IMD 14 may use its telemetry circuit 88 to communicate with externalprogrammer 20 via a first wireless connection, and to communication withan access point 128 via a second wireless connection. In other examples,IMD 26 may also be used in place of IMD 14, and external programmer 20may be either patient programmer 30 or clinician programmer 60.

In the example of FIG. 7, access point 128, external programmer 20,server 122, and computing devices 124A-124N are interconnected, and ableto communicate with each other, through network 126. In some cases, oneor more of access point 128, external programmer 20, server 122, andcomputing devices 124A-124N may be coupled to network 126 through one ormore wireless connections. IMD 14, external programmer 20, server 122,and computing devices 124A-124N may each comprise one or moreprocessors, such as one or more microprocessors, digital signalprocessors (DSPs), application specific integrated circuits (ASICs),field programmable gate arrays (FPGAs), programmable logic circuitry, orthe like, that may perform various functions and operations, such asthose described in this disclosure.

Access point 128 may comprise a device, such as a home monitoringdevice, that connects to network 126 via any of a variety ofconnections, such as telephone dial-up, digital subscriber line (DSL),or cable modem connections. In other embodiments, access point 128 maybe coupled to network 126 through different forms of connections,including wired or wireless connections.

During operation, IMD 14 may collect and store various forms of data.For example, IMD 14 may collect sensed posture state information duringtherapy that indicate how patient 12 moves throughout each day. In somecases, IMD 14 may directly analyze the collected data to evaluate theposture state of patient 12, such as what percentage of time patient 12was in each identified posture. In other cases, however, IMD 14 may sendstored data relating to posture state information to external programmer20 and/or server 122, either wirelessly or via access point 128 andnetwork 126, for remote processing and analysis. For example, IMD 14 maysense, process, trend and evaluate the sensed posture state information.This communication may occur in real time, and network 126 may allow aremote clinician to review the current patient posture state byreceiving a presentation of a posture state indication on a remotedisplay, e.g., computing device 124A. Alternatively, processing,trending and evaluation functions may be distributed to other devicessuch as external programmer 20 or server 122, which are coupled tonetwork 126. In addition, posture state information may be archived byany of such devices, e.g., for later retrieval and analysis by aclinician.

In some cases, IMD 14, external programmer 20 or server 122 may processposture state information or raw data and/or therapy information into adisplayable posture state report, which may be displayed via externalprogrammer 20 or one of computing devices 124A-124N. The posture statereport may contain trend data for evaluation by a clinician, e.g., byvisual inspection of graphic data. In some cases, the posture statereport may include the number of activities patient 12 conducted, apercentage of time patient 12 was in each posture state, the averagetime patient 12 was continuously within a posture state, what group orprogram was being used to deliver therapy during each activity, thenumber of adjustments to therapy during each respective posture state,or any other information relevant to patient 12 therapy, based onanalysis and evaluation performed automatically by IMD 14, externalprogrammer 20 or server 122. A clinician or other trained professionalmay review and/or annotate the posture state report, and possiblyidentify any problems or issues with the therapy that should beaddressed. Further, server 122 may process therapy adjustmentinformation and generate suggested therapy parameters for each programand posture state based upon the therapy adjustment information. If aguided algorithm is computationally intensive, server 122 may be bestsuited for generating the necessary parameters for therapy.

Using system 120 of FIG. 7, a clinician, physician, technician, or evenpatient 12, may review therapy adjustment information from the recordmode of IMD 14. The user may remotely monitor the progress and trends ofpatient 12, limiting the number of times that patient 12 may need tophysically visit the clinician. This monitoring may also reduce the timeneeded to find efficacious therapy parameters by allowing the clinicianto more frequently monitor how patient 12 is using patient programmer 30and how often changes to therapy must be made. Any of the userinterfaces described herein with respect to patient programmer 30 orclinician programmer 60 may also be presented via any of computingdevices 124A-124N.

In some cases, server 122 may be configured to provide a secure storagesite for archival of posture state information that has been collectedfrom IMD 14 and/or external programmer 20. Network 126 may comprise alocal area network, wide area network, or global network, such as theInternet. In some cases, external programmer 20 or server 122 mayassemble posture state information in web pages or other documents forviewing by trained professionals, such as clinicians, via viewingterminals associated with computing devices 124A-124N. System 120 may beimplemented, in some aspects, with general network technology andfunctionality similar to that provided by the Medtronic CareLink®Network developed by Medtronic, Inc., of Minneapolis, Minn.

Although some examples of the disclosure may involve posture stateinformation and data, system 120 may be employed to distribute anyinformation relating to the treatment of patient 12 and the operation ofany device associated therewith. For example, system 120 may allowtherapy errors or device errors to be immediately reported to theclinician. In addition, system 120 may allow the clinician to remotelyintervene in the therapy and reprogram IMD 14, patient programmer 30, orcommunicate with patient 12. In an additional example, the clinician mayutilize system 120 to monitor multiple patients and share data withother clinicians in an effort to coordinate rapid evolution of effectivetreatment of patients. Further, posture state detection may also be usedto provide notifications, such as providing notification via a wirelesslink to a care giver that a patient has potentially experienced a fall.

Furthermore, although the disclosure is described with respect to SCStherapy, such techniques may be applicable to IMDs that convey othertherapies in which posture state information is important, such as,e.g., DBS, pelvic floor stimulation, gastric stimulation, occipitalstimulation, functional electrical stimulation, and the like. Also, insome aspects, techniques for evaluating posture state information, asdescribed in this disclosure, may be applied to IMDs that are generallydedicated to sensing or monitoring and do not include stimulation orother therapy components. For example, an implantable monitoring devicemay be implanted in conjunction with an implantable stimulation device,and be configured to evaluate sensing integrity of leads or electrodesassociated with the implantable monitoring device based on sensedsignals evoked by delivery of stimulation by the implantable stimulationdevice.

FIGS. 8A-8C are conceptual illustrations of posture state spaces 140,152, 155 within which posture state reference data may define theposture state of patient 12. Posture state reference data may definecertain regions associated with particular posture states of patient 12within the respective posture state spaces 140, 152, 155. The output ofone or more posture state sensors may be analyzed by posture statemodule 86 with respect to posture state spaces 140, 152, 155 todetermine the posture state of patient 12. For example, if the output ofone or more posture state sensors is within a particular posture regiondefined by posture state reference data, posture state module 86 maydetermine that patient 12 is within the posture state associated withthe respective posture state region.

In some cases, one or more posture state regions may be defined asposture state cones. Posture state cones may be used to define a posturestate of patient 12 based on the output from a posture state sensor of aposture state according to an example method for posture statedetection. A posture state cone may be centered about a posture statereference coordinate vector that corresponds to a particular posturestate. In the examples of FIGS. 8A and 8B, the posture state module 86of IMD 14 or IMD 26 may use a posture state sensor, e.g., a three-axisaccelerometer that provides data indicating the posture state of patient12, to sense posture vectors.

While the sensed data may be indicative of any posture state, posturesof patient 12 will generally be used below to illustrate the concept ofposture cones. As shown in FIG. 8A, posture state space 140 represents avertical plane dividing patient 12 from left and right sides, or thesagittal plane. A posture state parameter value from two axes of theposture state sensor may be used to determine the current posture stateof patient 12 according to the posture state space 140. The posturestate data may include x, y and z coordinate values.

A posture cone may be defined by a reference coordinate vector for agiven posture state in combination with a distance or angle defining arange of coordinate vectors within a cone surrounding the posturereference coordinate vector. Alternatively, a posture cone may bedefined by a reference coordinate vector and a range of cosine valuescomputed using the reference coordinate vector as an adjacent vector andany of the outermost vectors of the cone as a hypotenuse vector. If asensed posture state vector is within an applicable angle or distance ofthe reference coordinate vector, or if the sensed posture state vectorand the reference coordinate vector produce a cosine value in aspecified cosine range, then posture state vector is determined toreside within the posture cone defined by the reference coordinatevector.

Posture state space 140 is segmented into different posture cones thatare indicative of a certain posture state of patient 12. In the exampleof FIG. 8A, upright cone 142 indicates that patient 12 is sitting orstanding upright, lying back cone 148 indicates that patient 12 is lyingback down, lying front cone 144 indicates that patient 12 is lying chestdown, and inverted cone 146 indicates that patient 12 is in an invertedposition. Other cones may be provided, e.g., to indicate that patient 12is lying on the right side or left side. For example, a lying rightposture cone and a lying left posture cone may be positioned outside ofthe sagittal plane illustrated in FIG. 8A. In particular, the lyingright and lying left posture cones may be positioned in a coronal planesubstantially perpendicular to the sagittal plane illustrated in FIG.8A. For ease of illustration, lying right and lying left cones are notshown in FIG. 8A.

Vertical axis 141 and horizontal axis 143 are provided for orientationof posture state area 140, and are shown as orthogonal for purposes ofillustration. However, posture cones may have respective posturereference coordinate vectors that are not orthogonal in some cases. Forexample, individual reference coordinate vectors for cones 142 and 146may not share the same axis, and reference coordinate vectors for cones144 and 148 may not share the same axis. Also, reference coordinatevectors for cones 144 and 148 may or may not be orthogonal to referencecoordinates vectors for cones 142, 146. Moreover, the referencecoordinate vectors need not reside in the same plane. Therefore,although orthogonal axes are shown in FIG. 8A for purposes ofillustration, respective posture cones may be defined by individualizedreference coordinate vectors for the cones.

IMD 14 may monitor the posture state parameter value of the posturestate sensor to produce a sensed coordinate vector and identify thecurrent posture of patient 12 by identifying which cone the sensedcoordinated vector of the posture state sensor module 86 resides. Forexample, if the posture state parameter value corresponds to a sensedcoordinate vector that falls within lying front cone 144, IMD 14determines that patient 12 is lying down on their chest. IMD 14 maystore this posture information as a determined posture state or as rawoutput from the posture state sensor, change therapy according to theposture, or both. Additionally, IMD 14 may communicate the postureinformation to patient programmer 30 so that the patient programmer canpresent a posture state indication to patient 12.

In addition, posture state area 140 may include hysteresis zones 150A,150B, 150C, and 150D (collectively “hysteresis zones 150”). Hysteresiszones 150 are positions within posture state area 140 where no posturecones have been defined. Hysteresis zones 150 may be particularly usefulwhen IMD 14 utilizes the posture state information and posture cones toadjust therapy automatically. If the posture state sensor indicates thatpatient 12 is in upright cone 142, IMD 14 would not detect that patient12 has entered a new posture cone until the posture state parametervalue indicates a different posture cone. For example, if IMD 14determines that patient 12 moves to within hysteresis zone 150A fromupright cone 142, IMD 14 retains the posture as upright. In this manner,IMD 14 does not change the corresponding therapy until patient 12 fullyenters a different posture cone. Hysteresis zones 150 prevent IMD 14from continually oscillating between different therapies when patient12's posture state resides near a posture cone boundary.

Each posture cone 142, 144, 146, 148 may be defined by an angle inrelation to a reference coordinate vector defined for the respectiveposture cone. Alternatively, some posture cones may be defined by anangle relative to a reference coordinate vector for another posturecone. For example, lying postures may be defined by an angle withrespect to a reference coordinate vector for an upright posture cone. Ineach case, as described in further detail below, each posture cone maybe defined by an angle in relation to a reference coordinate posturevector defined for a particular posture state. The reference coordinatevector may be defined based on posture sensor data generated by aposture state sensor while patient 12 occupies a particular posturestate desired to be defined using the reference coordinate vector. Forexample, a patient may be asked to occupy a posture so that a referencecoordinate vector can be sensed for the respective posture. In thismanner, vertical axis 141 may be specified according to the patient'sactual orientation. Then, a posture cone can be defined using thereference coordinate vector as the center of the cone.

Vertical axis 141 in FIG. 8A may correspond to a reference coordinatevector sensed while the patient was occupying an upright posture state.Similarly, a horizontal axis 143 may correspond to a referencecoordinate vector sensed while the patient is occupying a lying posturestate. A posture cone may be defined with respect to the referencecoordinate vector. Although a single axis is shown extending through theupright and inverted cones 142, 146, and another single axis is shownextending through the lying down and lying up cones 144, 148, individualreference coordinate vectors may be used for respective cones, and thereference coordinate vectors may not share the same axes, depending ondifferences between the reference coordinate vectors obtained for theposture cones.

Posture cones may be defined by the same angle or different angles,symmetrical to either axis, or asymmetrical to either axis. For example,upright cone 142 may have an angle of eighty degrees, +40 degrees to −40degrees from the positive vertical axis 141. In some cases, lying conesmay be defined relative to the reference coordinate vector of theupright cone 142. For example, lying up cone 148 may have an angle ofeighty degrees, −50 degrees to −130 degrees from the positive verticalaxis 141. Inverted cone 146 may have an angle of eighty degrees, −140degrees to +140 degrees from vertical axis 141. In addition, lying downcone 144 may have an angle of eighty degrees, +50 degrees to +130degrees from the positive vertical axis 141. In other examples, eachposture cone may have varying angle definitions, and the angles maychange during therapy delivery to achieve the most effective therapy forpatient 12.

Alternatively or additionally, instead of an angle, posture cones 144,146, 148, 148 may be defined by a cosine value or range of cosine valuesin relation to vertical axis 141, horizontal axis 143, or some otheraxis, such as, e.g., individual reference coordinate vectors for therespective cones. For example, a posture cone may be defined by a cosinevalue that defines the minimum cosine value, calculated using areference coordinate vector and a respective coordinate vector sensed bya posture state sensor at any point in time. In the cosine computation,the value (adjacent/hypotenuse) can be computed using the magnitude ofthe coordinate reference vector as the adjacent and a vector at theoutermost extent of the cone as the hypotenuse to define a range ofcosine values consistent with the outer bound of the cone.

For upright cone 142, the cosine range may extend from the maximumcosine value of 1.0, corresponding to a sensed vector that matches thereference coordinate vector of the upright cone, to a minimum cosinevalue that corresponds to a sensed vector at the outer limit of theupright cone. As another example, for lying cone 144, the cosine rangemay extend from the maximum cosine value of 1.0, corresponding to asensed vector that matches the reference coordinate vector of the lyingcone, to a minimum cosine value that corresponds to a sensed vector atthe outer limit of the lying cone. Alternatively, the lying cone 144 maybe defined with reference to the upright cone 142, such that the cosinerange may extend between a maximum and minimum values determinedrelative to the reference coordinate vector for the upright cone.

In other examples, posture state area 140 may include additional posturecones than those shown in FIG. 8A. For example, a reclining cone may belocated between upright cone 142 and lying back cone 148 to indicatewhen patient 12 is reclining back (e.g., in a dorsal direction). In thisposition, patient 12 may need a different therapy to effectively treatsymptoms. Different therapy programs may provide efficacious therapy topatient 12 when patient 12 is in each of an upright posture (e.g.,within upright cone 142), lying back posture (e.g., within lying backcone 148), and a reclining back posture. Thus, a posture cone thatdefines the reclining back posture may be useful for providingefficacious posture-responsive therapy to patient 12. In other examples,posture state area 140 may include fewer posture cones than cones 142,144, 146, 148 shown in FIG. 8A. For example, inverted cone 146 may bereplaced by a larger lying back cone 148 and lying front cone 144.

FIG. 8B illustrates an example posture state space 152 that is athree-dimensional space in which the posture state parameter value fromthe posture state sensor is placed in relation to the posture cones.Posture state space 152 is substantially similar to posture state area140 of FIG. 8A. However, the posture state parameter value derived fromall three axes of a 3-axis accelerometer may be used to accuratelydetermine the posture state of patient 12. In the example of FIG. 8B,posture state space 152 includes upright cone 154, lying back cone 156,and lying front cone 158. Posture state space 152 also includeshysteresis zones (not shown) similar to those of posture state area 140.In the example of FIG. 8B, the hysteresis zones are the spaces notoccupied by a posture cone, e.g., upright cone 154, lying back cone 156,and lying front cone 158.

Posture cones 154, 156 and 158 also are defined by a respective centerline 153A, 153B, or 153C, and associated cone angle A, B or C. Forexample, upright cone 154 is defined by center line 153A that runsthrough the center of upright cone 154. Center line 153A may correspondto an axis of the posture state sensor or some other calibrated vector.In some embodiments, each center line 153A, 153B, 153C may correspond toa posture reference coordinate vectors defined for the respectivepostures, e.g., the upright posture. For instance, assuming that patient12 is standing, the DC portion of the x, y, and z signals detected bythe posture state sensor of posture state module 86 define a posturevector that corresponds to center line 153A. The x, y, and z signals maybe measured while patient 12 is known to be in a specified position,e.g., standing, and the measured vector may be correlated with theupright posture state. Thereafter, when the DC portions of the posturestate sensor signal are within some predetermined cone tolerance orproximity, e.g., as defined by an angle, distance or cosine value, ofthe posture reference coordinate vector (i.e., center line 153A), it maybe determined that patient 12 is in the upright posture. In this manner,a sensed posture coordinate vector may be initially measured based onthe output of one or more posture state sensors of posture state module86, associated with a posture state, such as upright, as a referencecoordinate vector, and then later used to detect a patient's posturestate.

As previously indicated, it may be desirable to allow some tolerance tobe associated with a defined posture state, thereby defining a posturecone or other volume. For instance, in regard to the upright posturestate, it may be desirable to determine that a patient who is uprightbut leaning slightly is still in the same upright posture state. Thus,the definition of a posture state may generally include not only aposture reference coordinate vector (e.g., center line 153A), but also aspecified tolerance. One way to specify a tolerance is by providing anangle, such as cone angle A, relative to coordinate reference vector153A, which results in posture cone 154 as described herein. Cone angleA is the deflection angle, or radius, of upright cone 154. The totalangle that each posture cone spans is double the cone angle. The coneangles A, B, and C may be generally between approximately 1 degree andapproximately 70 degrees. In other examples, cone angles A, B, and C maybe between approximately 10 degrees and 30 degrees. In the example ofFIG. 8B, cone angles A, B, and C are approximately 20 degrees. Coneangles A, B, and C may be different, and center lines 153A, 153B, and153C may not be orthogonal to each other.

In some examples, a tolerance may be specified by a cosine value orrange of cosine values. The use of cosine values, in some cases, mayprovide substantial processing efficiencies. As described above, forexample, a minimum cosine value, determined using the referencecoordinate vector as adjacent and sensed coordinate vector ashypotenuse, indicates the range of vectors inside the cone. If a sensedcoordinate vector, in conjunction with the reference coordinate vectorfor a posture cone, produces a cosine value that is less than theminimum cosine value for the posture cone, the sensed coordinate vectordoes not reside within the pertinent posture cone. In this manner, theminimum cosine value may define the outer bound of a range of cosinevalues within a particular posture cone defined in part by a referencecoordinate vector.

While center lines 153A, 153B, 153C of each of the posture cones 154,156, 158, respectively, are shown in FIG. 8B as being substantiallyorthogonal to each other, in other examples, center lines 153A, 153B,and 153C may not be orthogonal to each other, and need not even residewithin the same plane. Again, the relative orientation of center lines153A, 153B, 153C may depend on the actual reference coordinate vectoroutput of the posture state sensor of posture state module 86 of IMD 14when patient 12 occupies the respective postures.

In some cases, all of the posture cones may be individually definedbased on actual reference coordinate vectors. Alternatively, in somecases, some posture cones may be defined with reference to one or morereference coordinate vectors for one or more other posture cones. Forexample, lying reference coordinate vectors could be assumed to beorthogonal to an upright reference coordinate vector. Alternatively,lying reference coordinate vectors could be individually determinedbased on sensed coordinate vectors when the patient is in respectivelying postures. Hence, the actual reference coordinate vectors fordifferent postures may be orthogonal or non-orthogonal with respect toone another, and need not reside within a same plane.

In addition to upright cone 154, lying back cone 156, and lying frontcone 158, posture state space 152 may include additional posture cones.For example, a lying right cone may be provided to define a patientposture in which patient 12 is lying on his right side and a lying leftcone may be provided to define a patient posture in which patient 12 islying on his left side. In some cases, the lying right cone and lyingleft cone may be positioned approximately orthogonal to upright cones154, in approximately the same plane as lying back cone 156 and lyingfront cone 158. Moreover, posture state space 152 may include aninverted cone positioned approximately opposite of upright cone 154.Such a cone indicates that the patient's posture is inverted from theupright posture, i.e., upside down.

In some examples, to detect the posture state of a patient, posturestate module 86 of IMD 14 may determine a sensed coordinate vector basedon the posture sensor data generated by one or more posture statesensors, and then analyze the sensed coordinate vector with respect toposture cones 154, 156, 158 of FIG. 8B. For example, in a case in whicha posture cone is defined by a reference coordinate vector and atolerance angle, e.g., tolerance angle “A,” posture state module 86 maydetermine whether the sensed coordinate vector is within upright posturecone 154 by calculating the angle between the sensed coordinate vectorand reference coordinate vector, and then determine whether the angle isless than the tolerance angle “A.” If so, posture state module 86determines that the sensed coordinate vector is within upright posturecone 154 and detects that patient 12 is in the upright posture. Ifposture state module 86 determines that sensed coordinate vector is notwithin upright posture cone 154, posture state module 86 detects thatpatient 12 is not in the upright posture.

Posture state module 86 may analyze the sensed coordinate vector inposture state space 152 with respect to each individual defined posturecone, such as posture cones 156 and 158, in such a manner to determinethe posture state of patient 12. For example, posture state module 86may determine the angle between the sensed coordinate vector andreference coordinate vector of individual posture cones defined for theposture state, and compare the determined angle to the tolerance angledefined for the respective posture cone. In this manner, a sensedcoordinate vector may be evaluated against each posture cone until amatch is detected, i.e., until the sensed coordinate vector is found toreside in one of the posture cones. Hence, a cone-by-cone analysis isone option for posture detection.

In other examples, different posture detection analysis techniques maybe applied. For example, instead of testing a sensed coordinate vectoragainst posture cones on a cone-by-cone basis, a phased approach may beapplied where the sensed coordinate vector is classified as eitherupright or not upright. In this case, if the sensed coordinate vector isnot in the upright cone, posture state module 86 may determine whetherthe sensed coordinate vector is in a lying posture, either by testingthe sensed coordinate vector against individual lying posture cones ortesting the sensed coordinate vector against a generalized lying posturevolume, such as a donut- or toroid-like volume that includes all of thelying postures, and may be defined using an angle or cosine rangerelative to the upright vector, or relative to a modified or virtualupright vector as will be described. In some cases, if lying posturesare defined by cones, the lying volume could be defined as a logical ORof the donut- or toroid-like volume and the volumes of the lying posturecones. If the cones are larger such that some portions extend beyond thelying volume, then those portions can be added to the lying volume usingthe logical OR-like operation.

If the sensed coordinate vector resides within the donut- or toroid-likelying volume, then the sensed coordinate vector may be tested againsteach of a plurality of lying posture cones in the lying volume.Alternatively, the posture detection technique may not use lying cones.Instead, a posture detection technique may rely on a proximity testbetween the sensed coordinate vector and each of the referencecoordinate vectors for the respective lying postures. The proximity testmay rely on angle, cosine value or distance to determine which of thelying posture reference coordinate vectors is closest to the sensedcoordinate vector. For example, the reference coordinate vector thatproduces the largest cosine value with the sensed coordinate vector ashypotenuse and the reference coordinate vector as adjacent is theclosest reference coordinate vector. In this case, the lying postureassociated with the reference coordinate vector producing the largestcosine value is the detected posture. Hence, there are a variety of waysto detect posture, such as using posture cones, using an upright posturecone with lying volume and lying posture cone test, or using an uprightposture cone with lying volume and lying vector proximity test.

As a further illustration of an example posture detection technique,posture state module 86 may first determine whether patient 12 isgenerally in a lying posture state or upright posture state by analyzingthe sensed coordinate vector in posture state space 152 with respect toan axis 153A for the upright posture state. Axis 153A may correspond tothe upright reference coordinate vector. For example, angle “A” may beused to define upright posture cone 154, as described above, and angles“D” and “E” may be used to define the vector space in which patient 12may be generally considered to be in the lying posture state, regardlessof the particular posture state cone, e.g., lying front cone 158, lyingback cone 156, lying right cone (not shown), or lying left cone (notshown), in which the sensed coordinate vector falls.

If it is determined that a sensed coordinate vector is not within anangle A of the axis 153A, then it may be determined that the patient isnot in the upright posture indicated by the upright posture cone. Inthis case, it may next be determined whether a sensed coordinated vectoris generally in a lying posture space volume, which may be consideredsomewhat donut- or toroid-like, and may be defined relative to theupright reference coordinate vector 153A. As shown, angles “D” and “E”define the minimum and maximum angle values, respectively, that a sensedvector may form with respect to axis 153A of patient 12 for adetermination to be made that the patient is generally in the lyingposture state. Again, cosine values may be used instead of angles todetermine the positions of sensed coordinate vectors relative to posturecones or other posture volumes, or relative to reference coordinatevectors.

As illustrated, angles “D” and “E” may be defined with respect tovertical axis 153A (which may correspond to an upright referencecoordinate vector), which is the reference coordinate vector for theupright posture cone, rather than with respect to a reference coordinatevector of a lying posture state cone. If a sensed vector is within theangular range of D to E, relative to axis 153A, then it can bedetermined by posture state module 86 that the patient is generally in alying posture. Alternatively, in some examples, an angle C could bedefined according to a generally horizontal axis 153C (which maycorrespond to one of the lying reference coordinate vectors). In thiscase, if a sensed vector is within angle C of axis 153C, it can bedetermined by posture state module 86 that the patient is in a lyingposture. In each case, the region generally defining the lying posturestate may be referred to as a posture donut or posture toroid, ratherthan a posture cone. The posture donut may generally encompass a rangeof vectors that are considered to be representative of various lyingdown postures.

As an alternative, posture state module 86 may rely on cosine values ora range of cosine values to define the posture donut or toroid withrespect to axis 153A. When the sensed vector falls within the vectorspace defined by axis 153A and angles “D” and “E”, or produces a cosinevalue with the reference coordinate vector 153A in a prescribed range,posture state module 86 may determine that patient 12 is generally in alying posture state. For example, if the sensed vector and referencecoordinate vector 153 produce a cosine value in a first range, theposture is upright. If the cosine value is in a second range, theposture is lying. If the cosine value is outside of the first and secondranges, the posture may be indeterminate. The first range may correspondto the range of cosine values that would be produced by vectors inposture cone 154 defined by angle A, and the second range may becorrespond to cosine values that would be produced by vectors in theposture donut defined by angles D and E.

When the sensed vector fall within the vector space defined by axis 153Aand angles “D” and “E”, as indicated by angle or cosine value, posturestate module 86 may then determine the particular lying posture stateoccupied by patient 12, e.g., lying front, lying back, lying right, orlying left. To determine the particular lying posture state occupied bypatient 12, posture state module 86 may analyze the sensed vector withrespect to reference coordinate vectors for individual lying posturestate cones, e.g., lying front cone 156, lying back cone 158, lyingright cone (not shown), and lying left cone (not shown), using one moretechniques previously described, such as angle or cosine techniques. Forexample, posture state module 86 may determine whether the sensedcoordinated vector resides within one of the lying posture state conesand, if so, select the posture state corresponding to that cone as thedetected posture state.

FIG. 8C illustrates an example posture state space 155 that is athree-dimensional space substantially similar to posture state space 152of FIG. 8B. Posture state space 155 includes upright posture cone 157defined by reference coordinate vector 167. The tolerance that definesupright posture cone 157 with respect to reference coordinate vector 167may include a tolerance angle or cosine value, as described above. Incontrast to determining whether a sensed coordinate vector resides in alying cone, FIG. 8C illustrates a method for detecting a lying posturebased on proximity of a sensed coordinate vector to one of the referencecoordinate vectors for the lying postures.

As shown in FIG. 8C, posture state space 155 includes four referencecoordinate vectors 159, 161, 163, 165, which are associated with lyingleft, lying right, lying front, and lying back posture states,respectively. Posture state module 86 may have defined each of the fourreference coordinated vector 159, 161, 163, 165 based on the output ofone or more posture sensors while patient 12 occupied each of thecorresponding posture states. Unlike lying front and lying back posturecones 158, 156 in the example of FIG. 8B, the posture state referencedata for the four defined posture states corresponding to referencevectors 159, 161, 163, 165 need not include angles defined relative tothe respective reference vector in a manner that defines a posture cone.Rather, as will be described below, the respective posture statereference vectors may be analyzed with respect to one another in termsof cosine values to determine which particular reference coordinatevector is nearest in proximity to a sensed coordinate vector.

In some examples, to determine the posture state of patient 12, posturestate module 85 may determine whether a sensed coordinate vector iswithin upright posture cone 157 by analyzing the sensed coordinatevector in view of the tolerance angle or cosine value(s) defined withrespect to upright posture reference coordinate vector 167, or whetherthe sensed vector is within a posture donut or toroid defined by a rangeof angles (as in FIG. 8B) or cosine values with respect to uprightposture reference coordinate vector 167, in which case posture statemodule 86 may determine that patient 12 is in a general lying posturestate.

If posture state module 86 determines that patient 12 is occupying ageneral lying posture state, posture state module 86 may then calculatethe cosine value of the sensed coordinate vector with respect to eachlying reference coordinate vectors 159, 161, 163, 165. In such a case,posture state module 86 determines the particular lying posture state ofpatient 12, i.e., lying left, lying right, lying front, lying back,based on which cosine value is the greatest of the four cosine values.For example, if the cosine value calculated with the sensed vector asthe hypotenuse and the lying front reference vector 163 as the adjacentvector is the largest value of the four cosine values, the sensed vectormay be considered closest in proximity to lying front reference vectorout of the four total reference vectors 159, 161, 163, 165. Accordingly,posture state module 85 may determine that patient 12 is occupying alying front posture state.

In some examples, posture state module 86 may determine whether patient12 is generally in a lying posture state based on the relationship of asensed vector to upright reference vector 167. For example, as describedabove, a lying posture donut or toroid may be defined with respect toupright posture reference vector 167, e.g., using angles D and E as inFIG. 8B. Such a technique may be appropriate when lying posturereference vectors 159, 161, 163, 165 define a common plane substantiallyorthogonal to upright posture reference vector 167. However, the lyingposture reference vectors 159, 161, 163, 165 may not in fact beorthogonal to the upright reference coordinate vector 167. Also, thelying posture reference vectors 159, 161, 163, 165 may not reside in thesame plane.

To account for non-orthogonal reference vectors, in other examples, alying posture donut or toroid may be defined with respect to a modifiedor virtual upright reference vector 169 rather than that actual uprightposture reference vector 167. Again, such a technique may be used insituations in which the lying reference vectors 159, 161, 163, 165 arenot in a common plane, or the common plane of reference vector 159, 161,163, 165 is not substantially orthogonal to upright reference vector167. However, use of the example technique is not limited to suchsituations.

To define virtual upright reference vector 169, posture state module 86may compute the cross-products of various combinations of lyingreference vectors 159, 161, 163, 165 and average the cross productvalues. In the example of FIG. 8C, posture state module 86 may computefour cross products and average the four cross product vectors to yieldthe virtual upright vector. The cross product operations that may beperformed are: lying left vector 159×lying back vector 165, lying backvector 165×lying right vector 161, lying right vector 161×lying frontvector 163, and lying front vector 163×lying left vector 159. Each crossproduct yields a vector that is orthogonal to the two lying referencevectors that were crossed. Averaging each of the cross product vectorsyields a virtual upright reference vector that is orthogonal to lyingplane 171 approximately formed by lying reference vectors 159, 161, 163,165.

Using virtual upright reference vector 169, posture state module 86 maydefine a lying posture donut or toroid in a manner similar to thatdescribed with respect to upright reference vector 167, but instead withrespect to virtual upright reference vector 169. In particular, whenposture state module 86 determines that the patient is not in theupright posture, the posture state module determines whether the patientis in a lying posture based on an angle or cosine value with respect tothe virtual upright reference vector 169.

Posture state module 86 may still determine whether patient 12 is in anupright posture state using upright posture cone 157. If posture statemodule 86 determines that patient 12 is occupying a general lyingposture state based on the analysis of the sensed coordinate vector withrespect to virtual upright reference vector 169, posture state module 86may then calculate the cosine value of the sensed coordinate vector (ashypotenuse) with respect to each lying reference coordinate vectors 159,161, 163, 165 (as adjacent).

In such a case, posture state module 86 determines the particular lyingposture state of patient 12, i.e., lying left, lying right, lying front,lying back, based on which cosine value is the greatest of the fourcosine values. For example, if the cosine value calculated with thelying front reference vector 163 is the largest value of the four cosinevalues, the sensed vector may be considered closest in proximity tolying front reference vector out of the four total reference vectors159, 161, 163, 165. Accordingly, posture state module 85 may determinethat patient 12 is occupying a lying front posture state.

Additionally, posture state definitions are not limited to posturecones. For example, a definition of a posture state may involve aposture vector and a tolerance, such as a maximum distance from theposture vector. So long as a detected posture vector is within thismaximum distance from the posture vector that is included in thedefinition of the posture state, patient 12 may be classified as beingin that posture state. This alternative method may allow posture statesto be detected without calculating angles, as is exemplified above inthe discussion related to posture cones.

Further to the foregoing, posture states may be defined that arespecific to a particular patient's activities and/or profession. Forinstance, a bank teller may spend a significant portion of his workingday leaning forward at a particular angle. A patient-specific “LeaningForward” posture state including this angle may be defined. The coneangle or other tolerance value selected for this posture state may bespecific to the particular posture state definition for this patient. Inthis manner, the defined posture states may be tailored to a specificuser, and need not be “hard-coded” in the IMD.

In some examples, individual posture states may be linked together,thereby tying posture states to a common set of posture reference dataand a common set of therapy parameter values. This may, in effect, mergemultiple posture cones for purposes of posture state-based selection oftherapy parameter values. For example, all lying posture state cones(back, front, left, right) could be treated as one cone or adonut/toroid, e.g., using a technique the same as or similar to thatdescribed with respect to FIGS. 8B and 8C to define a donut, toroid orother volume. One program group or common set of therapy parametervalues may apply to all posture states in the same merged cone,according to the linking status of the posture states, as directed viaexternal programmer 20.

Merging posture cones or otherwise linking a plurality of posture statestogether may be useful for examples in which a common set of therapyparameter values provides efficacious therapy to patient 12 for theplurality of posture states. In such an example, linking a plurality ofposture states together may help decrease the power consumption requiredto provide posture-responsive therapy to patient 12 because thecomputation required to track patient posture states and provideresponsive therapy adjustments may be minimized when a plurality ofposture states are linked together.

Linking of posture states also may permit a therapy parameter valueadjustment in one posture state to be associated with multiple posturestates at the same time. For example, the same amplitude level for oneor more programs may be applied to all of the posture states in a linkedset of posture states. Alternatively, the lying down posture states mayall reside within a “donut” or toroid that would be used instead ofseparate comes 156 and 158, for example. The toroid may be divided intosectional segments that each correspond to different posture states,such as lying (back), lying (front), lying (right), lying (left) insteadof individual cones. In this case, different posture reference data andtherapy parameter values may be assigned to the different sectionalsegments of the toroid.

FIG. 9 is a conceptual diagram illustrating an example user interface168 of a patient programmer 30 for delivering therapy information topatient 12. In other examples, a user interface similar to userinterface 168 may also be shown on clinician programmer 60. In theexample of FIG. 9, display 36 of patient programmer 30 provides userinterface 168 to the user, such as patient 12, via screen 170. Screen170 includes stimulation icon 174, IMD battery icon 176, programmerbattery icon 178, navigation arrows 180, automatic posture response icon182, group selection icon 184, group identifier 186, program identifier188, amplitude graph 190, and selection box 192. User interface 168provides information to patient 12 regarding group, program, amplitude,and automatic posture response status. User interface 168 may beconfigurable, such that more or less information may be provided topatient 12, as desired by the clinician or patient 12.

Selection box 192 allows patient 12 to navigate to other screens,groups, or programs using navigation arrows 180 to manage the therapy.In the example, of screen 170, selection box 192 is positioned so thatpatient 12 may use arrows 44 and 48 to move to the automatic postureresponse screen, the volume screen, the contrast or illumination screen,the time screen, and the measurement unit screen of patient programmer30. In these screens, patient 12 may be able to control the use of theautomatic posture response feature and adjust the patient programmer 30features. Patient 12 may only adjust the features surrounded byselection box 192.

Group identifier 186 indicates one of possibly several groups ofprograms that can be selected for delivery to patient 12. Groupselection icon 184 indicates whether the displayed group, e.g., group Bin FIG. 9, is actually selected for delivery to patient 12. If apresently displayed group is selected, group selection icon 184 includesa box with a checkmark. If a presently displayed group is not selected,group selection icon 184 includes a box without a checkmark. To navigatethrough the program groups, a user may use control pad 40 to moveselection box 192 to select the group identifier 186 and then usecontrol pad 40 to scroll through the various groups, e.g., A, B, C, andso forth. IMD 14 may be programmed to support a small number of groupsor a large number of groups, where each group contains a small number ofprograms or a large number of programs that are deliveredsimultaneously, in sequence, or on a time-interleaved basis.

For each group, group selection icon 184 indicates the appropriatestatus. For a given group, program identifier 188 indicates one of theprograms associated with the group. In the example of FIG. 9, no programnumber is indicated in program identifier 188 because all of theprograms' amplitudes are shown in each bar of amplitude graph 190. Solidportions of the bars indicate the relative amplitude IMD 14 currently isusing to deliver stimulation therapy to patient 12, while open portionsof the bars indicate the remaining amplitude available to each program.In some embodiments, numerical values of each program's amplitude may beshown in addition to or in place of amplitude graph 190. In otherembodiments of user interface 168 specific to drug delivery using IMD26, amplitude graph 190 may show the flow rate of drugs or frequency ofbolus delivery to patient 12. This information may be show in numericalformat as well. Patient 12 may encompass group selection icon 184 withselection box 192 to scroll between the different programs of theselected group.

Automatic posture response icon 182 indicates that IMD 14 is generallyactivated to automatically change therapy to patient 12 based upon theposture state detected by posture state module 86. In particularly,automatic posture responsive therapy may involve adjusting one or moretherapy parameter values, selecting different programs or selectingdifferent program groups based on the detected posture state of thepatient. However, automatic posture response icon 182 is not presentnext to group identifier 186. Therefore, group “B” does not haveautomatic posture responsive therapy activated for any of the programswithin group “B.”

Some groups or individual programs in groups may support automaticposture responsive therapy. For example, automatic adjustment of one ormore therapy parameters in response to posture state indication may beselectively activated or deactivated based on settings entered by aclinician, or possibly patient 12. Hence, some programs or groups may beconfigured for use with posture responsive therapy while other programsor groups may not be configured for use with posture responsive therapy.In some cases, if posture responsive therapy supported by the automaticposture response feature is desired, patient 12 may need to switchtherapy to a different group that has automatic posture responsivetherapy activated for IMD 14 to adjust therapy according to the patient12 posture state.

FIG. 10 is a conceptual diagram illustrating an example user interface168 of a patient programmer 30 for delivering therapy information thatincludes posture information to the patient. In other examples, userinterface 168 may also be shown on clinician programmer 60. In theexample of FIG. 10, display 36 of patient programmer 30 provides userinterface 168 to the user, such as patient 12, via screen 194. Screen194 includes stimulation icon 174, IMD battery icon 176, programmerbattery icon 178, and automatic posture response icon 182, similar toscreen 170 of FIG. 9. In addition, screen 194 includes group selectionicon 184, group identifier 186, supplementary posture state indication202, program identifier 196, posture state indication 200, amplitudevalue 204, selection box 192, and selection arrows 180. User interface168 provides information to patient 12 regarding group, program,amplitude, automatic posture response status, and posture stateinformation. More or less information may be provided to patient 12, asdesired by the clinician or patient 12.

Group identifier 186 indicates that group “B” is active, and automaticposture response icon 182 indicates group “B” (containing one or moreprograms) is activated to allow IMD 14 to automatically adjust therapyaccording to the posture state of patient 12. Specifically, the posturestate of patient 12 is the posture state in the example of FIG. 10.Program identifier 196 illustrates that information regarding program“1” of group “B” is displayed on screen 194, such as amplitude value 204illustrating the current voltage amplitude of program “1” is 2.85 Volts.Patient 12 may scroll through different programs of the group by usingnavigation arrows 180 via arrows 44 and 48 of control pad 40.

In addition, posture state indication 200 shows that IMD 14 has detectedthat patient 12 is in the upright or standing posture. Supplementaryposture state indication 202 supplements posture state indication 200 byillustrating in words to patient 12 the exact posture being detected byposture state module 86 of IMD 14. Posture state indication 200 andsupplementary posture state indication 202 change according to thesensed, or detected, posture state detected by IMD 14. The posture statemay be communicated to external programmer 20 immediately when IMD 14detects a posture change, or communicated periodically ornon-periodically by IMD 14 unilaterally or upon receiving a request fromprogrammer 20. Accordingly, the posture state indication 200 and/orsupplementary posture state indication 202 may represent a current,up-to-the minute status, or a status as of the most recent communicationof posture state from IMD 14. Posture state indication 200 is shown as agraphical representation, but the posture state indication mayalternatively be presented as any one of a symbolic icon, a word, aletter, a number, an arrow, or any other representation of the posturestate. In some cases, posture state indication 200 may be presentedwithout supplementary posture state indication 202.

Selection box 192 indicates that patient 12 view other programs withingroup “B” using selection arrows 208. Selection box 192 may be moved toselect other screen levels with control pad 40 in order to navigatethrough other stimulation groups or adjustable elements of the therapy.When patient 12 selects a different program with control pad 40, programidentifier 196 will change number to correctly identify the currentprogram viewed on screen 194.

In addition to graphical, textual or other visible indications ofposture state, the external programmer may present audible and/ortactile indications of posture state via any of a variety of audible ortactile output media. An audible indication may be spoken words statinga posture state, or different audible tones, different numbers of tones,or other audible information generated by the programmer to indicateposture state. A tactile indication may be, for example, differentnumbers of vibratory pulses delivered in sequence or vibratory pulses ofdifferent lengths, amplitudes, or frequencies.

FIG. 11A is a conceptual diagram illustrating an example user interface208 for orienting the implantable medical device prior to diagnostic ortherapy use. User interface 208 is described as generally beingdisplayed by clinician programmer 60. However, user interface 208 mayalso be displayed by patient programmer 30 or some other externalprogrammer 20 or remote device. In any case, user interface 208 displaysinformation related to sensing posture states, automatic postureresponse, reviewing recorded therapy adjustment information, andsuggested therapy parameters to increase therapy efficacy.

In the example of FIG. 11A, screen 210 of user interface 208 presentsorient information 236, operational menu 224, networking icon 214,printer icon 216, IMD communication icon 218, programmer battery icon220, stimulation status icon 222, patient data icon 226, data recordingicon 228, device status icon 230, programming icon 232, and datareporting icon 234. In addition, screen 210 includes posture stateselections 238A, 238B, 238C, 238D, and 238E (collectively “posture stateselections 238”), reset button 240, help button 242, and orient button244. Screen 210 may be accessed by selecting programming icon 232 toopen a drop down menu that allows the user to select one of multipledifferent screens. The user may select “orient device” or some othertext or icon that symbolizes access to the process for initializing theorientation of the posture state sensor within IMD 14.

Screen 210 includes multiple menus and icons common to other screens ofuser interface 208. Operational menu 224 is a button that the user mayselect to view multiple options or preferences selectable by the user.Operational menu 224 may provide preferences for clinician programmer 60instead of therapy specific information. Networking icon 214 is shown asgrayed out to indicate that clinical programmer 60 is not currentlyconnected to a network. When networking icon 214 is shown fully,clinician programmer 60 is connected to a network. Printer icon 216indicates when clinician programmer 60 is connected to a printer. Whenprinter icon 216 is grayed out as shown in FIG. 11A, there is no printerconnected to clinician programmer 60.

Further, IMD communication icon 218 is shown as indicating thatclinician programmer is not in communication with IMD 14 because theicon includes a slash through the IMD representation. The slash isremoved when clinician programmer 60 has established a communicationlink to IMD 14. In addition, programmer battery icon 220 indicates thecurrent charge level of the battery contained within clinicianprogrammer 60. Stimulation status icon 222 indicates to the user whenstimulation is being delivered to patient 12. Stimulation is notcurrently being delivered, but stimulation status icon 222 may includean electrical bolt through the IMD representation when stimulation isdelivered.

Screen 210 also provides menu options related to stimulation therapy ofpatient 12. Patient data icon 226 allows the user to enter and reviewdata related to the status of and the condition of patient 12. Datarecording icon 228 allows the user to navigate to other screens to enterdata recording preferences and review stored data. Device status icon230 allows the user to view operational status of components of IMD 14,such as electrodes, leads, batteries, and any discovered problems.Programming icon 232 allows the user to navigate to programming screensthat define the stimulation therapy parameters used to deliverstimulation to patient 12. In addition, data reporting icon 234 allowsthe user to view and print reports of patient 12 progress and othertherapy information.

Specific to screen 210 of user interface 208, the clinician mayinitialize the orientation of the posture state sensor of IMD 14 byhelping patient 12 assume each of posture state selections 238 andsetting the output of the posture state sensor to that particularposture state selection. Orient information 236, while not necessary inall examples, is provided to instruct the clinician on how to orient IMD14 to patient 12. For example, FIG. 11A shows that the clinician hasselected posture state selection 238A. Once patient 12 has assumed thestanding position, the clinician would select orient button 244 to haveIMD 14 set the posture state sensor output to the standing posturestate. The clinician would repeat this process for each of posture stateselections 238, in any order that the clinician chooses. In otherexamples, the clinician may not need to orient IMD 14 to each of thefive posture state selections 238. IMD 14 may only require three posturestate selections, such as standing, one of lying back or lying front,and one of lying left and lying right.

The step of orienting IMD 14 may be necessary before IMD 14 is capableof accurately sensing or detecting any posture state engaged by patient12. Therefore, user interface 208 may prevent the clinician fromentering the record mode with IMD 14, for example, unless the clinicianhas oriented IMD 14 to patient 12. In this manner, any recordedassociations between therapy adjustments and posture states or automaticposture response therapy is completed appropriately.

FIG. 11B is a conceptual diagram illustrating an example user interface208 showing the user that orientation of the implantable medical deviceis complete. As shown in FIG. 11B, screen 246 of user interface 208indicates to the clinician that orientation of IMD 14 has been completedfor each of the posture state selections 238 as described in FIG. 11A.Each of the posture state selections 238 has a check mark through thegraphical posture state indication on the right side of screen 246 toindicate that each posture state selection 238 has been oriented.Further, orient button 244 has been grayed out so that the cliniciancannot select it. Once clinician programmer 60 is presented with screen246, the clinician may move on to start the record mode, set programsfor each posture state, or any other programming task that requiressensing of the posture state of patient 12. In alternative examples,clinician programmer 60 may automatically begin the record mode and anyother posture state related applications once IMD 14 has been orientedto patient 12. For example, objectification and record modes may beautomatically turned on once the orientation process is completed.

FIGS. 12A and 12B are conceptual diagrams illustrating an example userinterface to determine orientation of an implantable medical devicewithout requiring a patient to occupy each posture state fororientation. FIGS. 12A and 12B illustrate example screens 211 and 247 ofuser interface 208 that are substantially similar to screens 210 and 246of FIGS. 11A and 11B. However, the example of FIGS. 12A and 12B onlyrequire that patient 12 assumes four posture states of the possible fiveposture states in order to orient IMD 14 to patient 12.

As shown in FIG. 12A, screen 211 of user interface 208 presents orientinformation 237, posture state selections 239A, 239B, 239C, 239D, and239E (collectively “posture state selections 239”), position button 241,and orient button 245. The user may select “orient device” or some othertext or icon that symbolizes access to the process for initializing theorientation of the posture state sensor within IMD 14.

Screen 211 allows the clinician to initialize the orientation of theposture state sensor of IMD 14 by helping patient 12 assume some of thepossible posture states that IMD 14 may detect. Once patient 12 hasassumed the appropriate types of posture states indicated by posturestate selections 239, the posture state sensor of IMD 14 will beoriented, or calibrated, with pertinent reference coordinate vectors tofunction as described in this disclosure.

The reference coordinate vectors may be used to define posture cones fordifferent posture states for some posture detection techniques. In someexamples, a reference coordinate vector may be used to define an uprightcone, and then lying reference coordinate vectors for each of the lyingposture states may be used to define lying posture cones, or simply useddirectly as vectors for cosine- or angle-based proximity testing in someposture detection techniques.

In the example of FIG. 12A, the clinician has not selected the posturestate that patient 12 will first assume. Although there are fivepossible posture states, screen 211 only requires that patient 12 assumefour of the five posture states. In any particular order, the clinicianorients IMD 14 to the upright position indicated by posture stateselection 239A, just one of the lying back or lying front posture statesindicated by posture state selections 239B and 239C, the lying leftposture state indicated by posture state selection 239D, and the lyingright posture state indicated by posture state selection 239E.

The clinician may orient each of these posture states by clicking on theappropriate posture state selection 239, ensuring that patient 12 hasassumed that particular posture state, and selecting orient button 245.A sensed coordinate vector is then assigned to the posture stateselection as a reference coordinate vector for use in posture detectionaccording to any of the posture detection techniques described in thisdisclosure. At any time, the clinician may check in which posture statethat IMD 14 is detecting patient 12 by selecting position button 241.Upon selecting position button 241, user interface 208 may provide anindication of the current posture state of patient 12. Once each ofthese posture states is oriented, therapy may proceed as described inthis disclosure.

As shown in FIG. 12B, screen 247 of user interface 208 indicates to theclinician that orientation of IMD 14 has been completed for each of theposture state selections 239 as described in FIG. 12A. Each of theposture state selections 239 has a check mark through the graphicalposture state indication on the right side of screen 247 to indicatethat each posture state selection 239 has been oriented. It should benoted that in an example wherein a lying back posture state is an“opposite” of the lying front posture sate, once either the lying backor lying front posture state has been oriented, both posture stateselections 239B and 239C will be checked as completed.

In particular, in an example wherein the reference coordinate vectorsfor the lying back and lying front posture states are in exactlyopposite directions from one another, once a reference coordinate vectoris obtained for one of the lying front or lying back posture states, theinverse of that reference coordinate vector may be used for the other ofthe lying front or lying back posture states. For example, if thereference coordinate vector is obtained for the lying front posturestate, then the reference coordinate vector for the lying back posturestate is simply the inverse of the lying front reference coordinatevector, and the actual reference coordinate vector for the lying frontposture state need not be obtained. Further, as shown in FIG. 12B,orient button 245 has been grayed out so that the clinician cannotselect it.

Once clinician programmer 60 is presented with screen 247, the clinicianmay move on to start the record mode, set programs for each posturestate, or any other programming task that requires sensing of theposture state of patient 12. In alternative examples, clinicianprogrammer 60 may automatically begin the record mode and any otherposture state related applications once IMD 14 has been oriented topatient 12. For example, objectification and record modes may beautomatically turned on once the orientation process is completed.

FIG. 13 is a conceptual diagram illustrating example posture searchtimer 250 and posture stability timer 252 when patient 12 remains in oneposture state. As described herein, IMD 14 must be able to correctlyassociate each therapy adjustment with a therapy parameter to theintended posture state of patient 12 when the therapy adjustment wasmade. For example, patient 12 may make therapy adjustments to customizethe therapy either after patient 12 moves to a different posture stateor in anticipation of the next posture state. IMD 14 may employ posturesearch timer 250 and posture stability timer 252 to track therapyadjustments and the current posture state of patient 12. Although IMD 14may associate therapy adjustments of any therapy parameter to a posturestate, some examples of IMD 14 may only allow the association ofamplitude changes. In this manner, patient 12 may change differenttherapy parameters such as pulse width, pulse rate, or electrodeconfiguration, but IMD 14 will not store these therapy adjustments asbeing associated to any posture state in some examples.

Posture search timer 250 has a search period that is a set amount oftime that patient 12 has from the time the therapy adjustment is made,when posture search timer 250 starts, to when the final posture statemust begin, prior to the expiration of the search period. In otherwords, the therapy adjustment will not be associated with a posturestate entered after the search period has expired. In addition, posturestability timer 252 has a stability period that is a set amount of timethat patient 12 must remain within the final posture state for thetherapy adjustment made to be associated with the final posture state.Posture stability timer 252 restarts at any time that patient 12 changesposture states. In order to associate a therapy adjustment with aposture state, the stability timer for the posture state must startbefore the end of the search period, and the posture state must notchange during the stability period. Therefore, the search period andstability period must overlap for the therapy adjustment to beassociated with a posture state not currently engaged by patient 12 whenthe therapy adjustment was made.

In the example of FIG. 13, patient 12 made a therapy adjustment to oneof the therapy parameters, such as voltage or current amplitude, at timeT₀. Therefore, posture search timer 250 starts at T₀ and runs for apredetermined search period until time T₁. When the therapy adjustmentis made, posture stability timer 252 also starts at time T₀ in thecurrent posture state of patient 12 and runs for the stability period.In the example of FIG. 13, the stability period is the same as thesearch period. Since patient 12 has not changed to any different posturestates between times T₀ and T₁, the stability period also ends at T₁.The therapy adjustment made by patient 12 at time T₀ is associated withthe posture state sensed between times T₀ and T₁ because both the searchperiod and stability period overlap. In the example of FIG. 13, posturesearch timer 250 and posture stability timer 252 may not be needed, buttheir purpose may become clearer in the following examples.

The search period of posture search timer 250 may be of any timeduration desired by a device manufacturer, and the clinician may or maynot be permitted to set the search period to a desired value or within apredetermined search range. Generally, the search period may be betweenapproximately 30 seconds and 30 minutes, but it may be set to any timedesired, including a time that is outside of that range. Morespecifically, the search period may be between approximately 30 secondsand 5 minutes, or more preferably 2 minutes to 4 minutes in order toprovide a reasonable amount of time for patient 12 to be situated in thefinal desired posture state. In some examples, and as described in theexamples of FIGS. 13-17, the search period is approximately 3 minutes.In other cases, shorter search periods may be used, e.g., approximately1 second to 60 seconds, or approximately 5 seconds to 20 seconds.

In addition, the stability period of posture stability timer 252 may beof any time duration desired by the manufacturer or clinician, where theclinician may or may not be permitted to set the stability period.Generally, the stability period is between approximately 30 seconds and30 minutes, but it may be set to any time desired, including timesoutside of that range. More specifically, the stability period may bebetween approximately 30 seconds and 5 minutes, and more preferably 2minutes to 4 minutes, in order to ensure that patient 12 is situated inthe final desired posture state for a reasonable amount of time and thatthe final posture state is not just some transitional or interim posturestate. In some examples, and as described in the examples of FIGS.13-17, the stability period is approximately 3 minutes. Although thesearch period and stability period may have the same duration, they maybe different in other examples. In other cases, shorter stabilityperiods may be used, e.g., approximately 1 second to 60 seconds, orapproximately 5 seconds to 20 seconds.

As one illustration, reliable association results may be achieved usinga search period of approximately 10 to 30 minutes, and a stabilityperiod of approximately 2 to 4 minutes, and more preferablyapproximately 3 minutes. Search and stability periods in these rangesshould be effective in supporting reliable associations of patienttherapy adjustments with posture states over a range of typical patientbehavior. However, other ranges of stability period and search periodmay be used and, in some cases, search and stability timer ranges may becustomized for individual patients.

As described herein, associating therapy adjustments with intendedposture states allow the user to review the types of therapy adjustmentspatient 12 made while assuming, or transitioning to, each posture state.However, the associations may also be used to update therapy parametersused by programs and groups to define the stimulation therapy deliveredto patient 12, instead of, or in addition to, simply storing themultiple associations for later review. For example, IMD 14 maydetermine that a therapy adjustment made by patient 12 to increase theamplitude of the current program is associated with the next posturestate assumed by patient 12. IMD 14 may then update and set the programto the associated therapy parameter.

In this case, the next time patient 12 engages in the same posture stateas the association, IMD 14 will deliver stimulation therapy according tothe increased amplitude made by patient 12 due to the association.Therefore, IMD 14 may use posture search timer 252 and posture stabilitytimer 254 to learn or update program therapy parameters such that IMD 14remembers the previous therapy parameters of therapy delivery forsubsequent delivery according to the engaged posture state. In general,upon detection of a patient adjustment to electrical stimulation therapydelivered to the patient, and sensing of a posture state of the patient,the adjustment is associated with the sensed posture state if the sensedposture state is sensed within a search period following the detectionof the adjustment and if the sensed posture state does not change duringa stability period following the sensing of the sensed posture state.

FIG. 14 is a conceptual diagram illustrating example posture searchtimer 254 and posture stability timer 256 with one change in posturestate. As shown in FIG. 14, patient 12 makes an anticipatory therapyadjustment for the next posture state that patient 12 does not currentlyoccupy. In other words, patient 12 makes a therapy adjustment that thepatient may believe is desirable for a given posture in anticipation oftransitioning to that posture on an imminent or near-term basis. Posturesearch timer 254 and posture stability timer 256 start at time T₀ whenpatient 12 makes a therapy adjustment in a current posture stateoccupied at time T₀. At time T₁, patient 12 changes to a second posturestate that is different than the initial posture state occupied at timeT₀. Therefore, posture stability timer 256 restarts at time T₁, with thechange to the new posture state, still within the search duration ofposture search timer 254.

In general, patient therapy adjustments received during the searchperiod restart the search period. As a result, a series of patienttherapy adjustments that are entered closely in time are, in effect,clustered together such that intermediate adjustments are not associatedwith the posture state. Instead, the last adjustment in a series ofclosely spaced (in time) adjustments may be associated with the posturestate to represent the final adjustment that brought the parameter to alevel or value deemed appropriate by the patient 12 for the givenposture state. If the search period is three minutes, for example, andthe patient 12 makes four adjustments in voltage amplitude within threeminutes of one another, e.g., 4.6 volts to 4.8 volts, 4.8 volts to 5.0volts, 5.0 volts to 5.1 volts, 5.1 volts to 5.3 volts, then the finaladjustment value of 5.3 volts may be associated with the posture state.Each time that a new adjustment is entered within the search period, thesearch period is reset. Once the final adjustment is made, however, ifthere are no further adjustments for another three minutes, and thestability period is satisfied for the detected posture state, then thefinal adjustment is associated with the posture state.

Time T₂ indicates the end of posture search timer 254. Consequently, theonly posture state that processor 80 of IMD 14 will associate with thetherapy adjustment is the second posture state as long as the secondposture state satisfies the stability period of posture stability timer256, i.e., the patient occupies the second posture state for thestability period. At time T₃, patient 12 is still in the second posturewhen the stability period ends, and the therapy adjustment is associatedthen to the second posture state because the stability period overlappedwith the search period.

It should be noted that patient 12 may make additional therapyadjustments within the search period. If this occurs, any previoustherapy adjustments made before the search period or stability period iscompleted are not associated to any posture state. Therefore, both thesearch period and stability period must lapse, i.e., expire, in orderfor a therapy adjustment to be associated with a posture state. However,in some examples, IMD 14 may allow therapy adjustments to be associatedwith posture states as long as the search period has lapsed or nodifferent posture state was sensed during the search period.

FIG. 15 is a conceptual diagram illustrating example posture searchtimer 258 and posture stability timer 260 with two changes in posturestates. As shown in FIG. 15, patient 12 makes an anticipatory therapyadjustment but is engaged in an interim posture state before settlinginto the final posture state. Posture search timer 258 and posturestability timer 260 both start at time T₀ when patient 12 makes atherapy adjustment in a current posture state engaged at time T₀.

At time T₁, patient 12 changes to a second posture state, or an interimposture state, that is different than the initial posture state engagedat time T₀. Therefore, posture stability timer 260 restarts at time T₁,still within the search duration of posture search timer 258. At timeT₂, patient 12 changes to a third posture state, and again posturestability timer 260 restarts. Time T₃ indicates the end of posturesearch timer 258, so the only posture state that processor 80 of IMD 14will associate with the therapy adjustment is the third posture statebegun at time T₂ as long as the third posture state satisfies thestability period of posture stability timer 260. At time T₄, patient 12is still in the third posture when the stability period ends, and thetherapy adjustment is associated then to the third and final posturestate because the stability period of the third posture state overlappedwith the search period.

FIG. 16 is a conceptual diagram illustrating example search timer 262and posture stability timer 264 with the last posture state changeoccurring outside of the posture search timer. As shown in FIG. 16,patient 12 makes an anticipatory therapy adjustment but is engaged in aninterim posture state too long before settling into the final posturestate for the therapy adjustment to be associated with any posturestate. Posture search timer 262 and posture stability timer 264 bothstart at time T₀ when patient 12 makes a therapy adjustment in a currentposture state engaged at time T₀. At time T₁, patient 12 changes to asecond posture state, or an interim posture state, that is differentthan the initial posture state engaged at time T₀. Therefore, posturestability timer 264 restarts at time T₁, still within the searchduration of posture search timer 262.

However, the search timer expires at time T₂, before patient 12 changesto a third posture state at time T₃, when posture stability timer 264again restarts. The stability period for the third posture state thenexpires at time T₄. Since the third posture state did not start beforethe search period expired at time T₂, the search period and stabilityperiod do not overlap and the therapy adjustment from time T₀ is notassociated to any posture state. In other examples, therapy adjustmentsmay still be associated with the posture state occupied at time T₀ whenthe search period and last stability period do not overlap.

The following is a further illustration of the example described in FIG.16 to put the example in context of an example patient scenario. Patient12 may be engaged in the upright posture state when patient 12 makes thetherapy adjustment at time T₀. In this example, the search duration isthree minutes and the stability duration is also three minutes. Aftertwo minutes, or at time T₁, patient 12 transitions to the lying leftposture to cause processor 80 of IMD 14 to restart posture stabilitytimer 260.

If patient 12 remains within the lying left posture for the full threeminutes of the stability duration, then the therapy adjustment would beassociated with the lying left posture. However, patient 12 leaves thelying left posture after only two minutes, or at time T₃, outside of thesearch duration. At this point the therapy amplitude made at time T₀,will not be associated with the next posture state of patient 12.Therefore, the next posture state may be the lying back posture state.Once IMD 14 senses the lying back posture state, IMD 14 may changetherapy according to the therapy parameters associated with the lyingback posture because IMD 14 is operating in the automatic postureresponse mode. No new associations with the therapy adjustment would bemade in the example of FIG. 16.

FIG. 17 is a flow diagram illustrating an example method for associatinga received therapy adjustment with a posture state. In general, in arecord mode, IMD 14 or an external programmer 20 detecting patientadjustments to electrical stimulation therapy delivered to a patientduring multiple instances of a sensed posture state, and associating thedetected patient adjustments with the sensed posture state of thepatient. The associations can stored in memory for later retrieval toview associations and/or support various programming techniques forprogramming of therapy parameters for posture state-responsive therapy.Although the example of FIG. 17 will be described with respect topatient programmer 30 and IMD 14, the technique may be employed in anyexternal programmer 20 and IMD or other computing device. As shown inFIG. 17, user interface 106 receives the therapy adjustment from patient12 (266) and processor 80 of IMD 14 immediately starts the posturesearch timer (268) and the posture stability timer (270).

If the posture state of patient 12 does not change (272), processor 80checks to determine if the stability period has expired (276). If thestability period has not expired (276), processor 80 continues to sensefor a posture state change (272). If the stability period has expired(276), the processor 80 uses the final posture state, i.e., thecurrently sensed posture state, to select therapy parameters to delivertherapy (282). Processor 80 then associates the therapy adjustment withthe final posture state and retains the therapy adjustment for currenttherapy (284).

If processor 80 senses a posture state change (272), processor 80determines if the search period has expired (274). If the search periodhas not expired (274), then processor 80 restarts the posture stabilitytimer (270). If the search period has expired (274), then processor 80delivers therapy to patient 12 according to the current posture state(278). Processor 80 retains the therapy adjustment and does notassociate the therapy adjustment with the final posture state becausethe search period did not overlap with the stability period (280). Usingthe search and stability timers, each of the detected adjustments isassociated with a sensed posture state if the sensed posture state issensed within a search period following the detection of the adjustmentand if the sensed posture state does not change during a stabilityperiod following the sensing of the sensed posture state.

In some examples, as an alternative, a posture stability timer may beemployed without the use of a posture search timer. As described withrespect to posture stability timer 260, the posture stability timer maybe started after a therapy adjustment and reset each time patient 12changes posture states prior to expiration of the posture stabilitytimer. When the posture stability timer 260 expires, the therapyadjustment may be associated with the posture state that patient 12 isoccupying at that time. In this manner, the therapy adjustment may beassociated with the first stable posture state, i.e., the first posturestate that remains stable for the duration of the posture stabilitytimer, after the therapy adjustment, regardless of the amount of timethat has past since the therapy adjustment. Hence, in someimplementations, processor 80 may apply only a stability timer without asearch timer. In some cases, the use of only a stability timer, withouta search timer, may be approximated by setting the search timer value toa large value, such as 24 hours. The effect of a very large search timervalue is to operate with only a stability timer.

It should be noted that, in an example implementation, processor 80 maynot change therapy to patient 12 at any time until the stability periodexpires. In other words, the posture stability timer may runindependently of the posture search timer to always track posture statesindependently of therapy adjustments. Therefore, IMD 14 may not performany automatic posture state-responsive stimulation until the posturestate of patient 12 is stable and the stability period has expired. Inthis manner, patient 12 may not be subjected to rapidly changing therapywhen transitioning between multiple posture states. Alternatively, IMD14 may employ a separate posture stability timer for changing therapyduring automatic posture response from the therapy adjustment relatedposture stability timer described herein.

FIG. 18 is a conceptual diagram illustrating an example user interface208 for initiating the record mode that stores therapy adjustments foreach posture state. As shown in FIG. 18, screen 286 of user interface208 allows the clinician to initiate or enable the record mode thatassociates therapy adjustments to posture states and stores theassociations within IMD 14 and/or external programmer 20. FIG. 18 is anexample of clinician programmer 60 displaying user interface 208, butany programmer 20 may be used. Record mode selection 288 is checked toshow that the clinician desires to initiate the record mode. Theclinician also has the opportunity in screen 286 to enable and storeobjectification data related to posture state information. As mentionedpreviously, objectification data may be automatically stored unless theclinician turns off that application. For example, objectificationand/or record modes may be automatically turned on once the orientationprocess is completed.

Screen 286 may also allow the clinician to check the orientation of theposture state sensor of IMD 14 by selecting posture button 292. Thecurrent posture would then be displayed in posture field 294. In someexamples, the posture state of patient 12 may be presented as a pictureor icon of the patient body, posture state, the posture cone used, a twodimensional or three dimensional vector illustrating the position of thebody of the patient 12 relative to the cones, or simply the currentoutput coordinates of the posture state sensor. The clinician may alsobe able to turn on or suspend the automatic posture responsivestimulation that changes therapy based upon the sensed posture state ofpatient 12, with posture control button 296. After the clinician checksto enable the record mode selection 288, the clinician may selectprogram button 300 to enable the record mode. Alternatively, theclinician may select clear button 298 to erase any selections on screen286.

FIGS. 19-26 are directed to clinician programmer 60, but could also bedirected to any other external programmer 20. FIG. 19 is a conceptualdiagram illustrating an example user interface 208 showing storedadjustment information and allowing programming with a singleconfirmation input, i.e., one-click programming. As shown in FIG. 19,screen 302 of user interface 208 presents associated therapy adjustmentinformation in addition to allowing the clinician to set a nominaltherapy parameter for a plurality of programs with a single confirmationinput. Screen 302 includes group menu 304, posture state menu 306,therapy adjustment information 308, confirmation button 318, and summarybutton 320.

In general, screen 302 presents therapy adjustment information to auser. The therapy adjustment information includes one or more therapyadjustments made by a patient to at least one stimulation parameter ofone or more stimulation therapy programs for one or more patient posturestates. Upon receiving input from the user that selects one or morenominal therapy parameters for each of the therapy programs and for eachof the posture states based on the therapy adjustment information,programmer sets the selected nominal therapy parameters for each of thetherapy programs and posture states for use in delivering stimulationtherapy to the patient.

Group menu 304 allows the clinician to select the desired group ofprograms to be displayed on screen 302. The groups presented in groupmenu 304 may be static and not changeable during a programming sessionwith the clinician. However, some examples of user interface 208 mayallow newly added or deleted groups to be shown in updated group menu304. In addition, group menu 304 may only show groups in which automaticposture response is currently active. If a device with groups A, B and Cis interrogated, and then groups D and E are added during a programmingsession, the group list may not update in some configurations of theprogrammer and IMD. In other examples, however, the group list couldupdate automatically. The list could be filtered based on which groupsare enabled for posture-responsive therapy and which are not.

Currently, in the example of FIG. 19, the clinician has selected programgroup “C,” which is also the group currently selected to deliverstimulation therapy because of the quotation marks around the groupletter. Alternatively, the active group could be indicated with anyother indication representative that the group currently deliverstherapy. Posture state menu 306 also allows the clinician to select thedesired posture state so that the therapy adjustment information that ispresented is related to the selected posture state. In particular,therapy adjustment information may be displayed to indicate adjustmentsmade by the patient for a particular program while occupying aparticular posture state. In FIG. 19, the clinician has selected theupright posture state in posture state menu 306, and group C in thegroup menu 304. As a result, screen 302 of the programmer 60 presentsminimum and maximum values selected by the patient for the individualprograms in group C while the patient occupied the upright posturestate.

Therapy adjustment information 308 includes multiple fields that includedata derived from the therapy adjustment information stored within IMD14, patient programmer 30, or clinician programmer 60. Program field 310presents each program (C1, C2, C3) for the selected group (C).Adjustment field 312 presents the quantified number of adjustments(#Adj) patient 12 made for each of the programs for a given posturestate (e.g., Upright in FIG. 19). The number of adjustments may be atotal or an average over a specific time interval, such as an hour, day,week, or month, or over an open-ended time interval, such as a therapysession running between successive programming sessions, which may bein-clinic or remote programming sessions in which IMD 14 is programmedwith updating program parameters.

Minimum field 314 presents the minimum amplitude that patient 12adjusted for each program, and maximum field 316 presents the maximumamplitude that patient 12 adjusted for each program. Therefore, minimumfield 314 and maximum field 316 provide an amplitude range for eachprogram within which patient 12 received stimulation therapy whileoccupying a particular posture. For example, program C1 was used todeliver stimulation therapy with an amplitude between 5.5 volts (V) and5.9 V, where 5.5 volts was the minimum amplitude selected by the patientand 5.9 V was the maximum selected by the patient in the relevant timeinterval while occupying the relevant posture state (e.g., Upright inFIG. 19). The amplitude is provided in volts but IMD 14 alternativelymay deliver stimulation as constant current. However, if IMD 14 deliversstimulation with constant current, the amplitude instead may beindicative of a current amplitude displayed in amps.

With therapy adjustment information 308 presented to the clinician,screen 302 also allows the clinician to make changes to the therapyparameters of each of the programs shown on screen 302. In the exampleof FIG. 19, the nominal therapy parameter for a program is the minimumamplitude of the recorded therapy adjustments for that posture state.The clinician may desire to set all of the programs of group “C” totheir minimum amplitudes for the given posture by selecting confirmationbutton 318, a confirmation input, only one time. The nominal therapyparameter may be a therapy parameter selected from the therapyadjustments stored in the IMD. In other words, in this example, thenominal therapy adjustment is not weighted or calculated according to analgorithm. In this manner, programming time may be decreased because theclinician may be provided with a therapy parameter for programming andthe programming of a plurality of programs for a given posture state maybe completed with only a single click of confirmation button 318. Uponselecting summary button 320, clinician programmer 60 will presentadditional posture state information or therapy adjustment information,such as the total number of therapy adjustments associated with eachposture state, as shown in FIG. 24.

As illustrated in FIG. 19 and discussed above, by selecting programgroup via group menu 304 and posture state via posture state menu 306, auser can view a number of adjustments 312 by the patient, minimum values314 selected by the patient, and maximum values selected by the patientfor the programs C1-C3 in the program group and particular posturestates in which the adjustments were made. Hence, the user may view thisinformation for different program groups and different posture states,and then apply the pertinent minimum amplitude as the nominal amplitudefor the respective program and posture state, e.g., via confirmationbutton 318. Then, when posture responsive therapy is running, the IMD 14will deliver stimulation with the pertinent minimum amplitude when thepatient is applying the respective program while occupying therespective posture state.

Screen 302 only presents recorded amplitudes that were associated witheach posture state for each program, and may not show pulse width, pulserate and electrode configuration. However, screen 302 may alternativelybe configured to show other stimulation therapy parameter values inaddition to the amplitudes or provide a link for the user to view theadditional therapy parameters. Although only therapy adjustments toamplitude are associated and stored in IMD 14 in this example, othertherapy parameter adjustments may also be recorded in some examples. Theassociation of therapy adjustments could be performed for any one ormore of the therapy parameter values that define each program, and evennon-associated therapy parameters values may be presented to the uservia user interface 208. If only amplitude adjustments are used, it maybe implied that each amplitude adjustment assumes constant pulse width,pulse rate and electrode configuration for each amplitude adjustment. Inother examples, if patient 12 makes a change to pulse width, pulse rate,or electrode configuration during therapy, any associated amplitudes tothat changed program may be erased because the association of amplitudeare no longer based on the original therapy parameters used when theassociations were made.

In addition, screen 302 may not always allow the clinician to confirmtherapy parameter changes to groups or programs deleted and re-added totherapy since therapy adjustments were associated. In other words, thegroups and programs for which associations were made during use bypatient 12 can only be modified using the stored therapy adjustmentswhen the groups and programs presence for therapy is consistent.Further, if any leads, in the case of electrical stimulation, have beenreconfigured for therapy, user interface 208 may prevent the clinicianfrom making any changes to the therapy parameters using confirmationbutton 318. These restrictions of making changes to therapy may bedesired to prevent the clinician from making inappropriate changes totherapy.

Although screen 302 only shows the programs for one group at a time, andfor one posture state at a time, alternative examples of user interface208 may provide more than one group of programs and more than oneposture state at one time. Then, the clinician may be able to set moreof the therapy parameters for multiple groups of programs with a singleclick of confirmation button 318. In other examples, the clinician maybe able to select a global confirmation button (not shown) that sets thenominal therapy parameter for every program within IMD 14 with a singleclick of the global confirmation button.

Again, it may be implicit that the amplitudes that are recorded andshown have a constant pulse width, pulse rate, and electrodeconfiguration. If, during the course of a programming session, the userchanges the electrode configuration, pulse width, pulse rate or anyparameter that is not listed on this screen (because it was implicit),the confirmation button 318 may be grayed out for that group only,because the recorded amplitudes only were valid in conjunction with theimplicit pulse width, rate, and electrode configuration. If a group isdeleted and then re-added (e.g., B is deleted and then re-created), theconfirmation button 318 may be grayed for that group. If a program iseither added or deleted in a group, confirmation button 318 may begrayed out for that group. If the lead configuration is changed,confirmation button 318 may be grayed out for all groups used fortherapy.

FIG. 20 is a conceptual diagram illustrating an example user interface208 showing user selection of a program group. As shown in FIG. 20,screen 302 presents the therapy adjustment information from the recordmode. Specifically, group menu 304 is shown in the drop-down form thatallows the clinician to select which group of programs will be presentedon screen 302. In the example of FIG. 20, available groups are A, B, C,D, E, and F, but group menu 304 may have more or less groups dependingon how the clinician programmed stimulation therapy. In other examples,group menu 304 may be a scrollable list, a text field for the clinicianto enter the desired group, or some other menu that allows the clinicianto select the desired group. Alternatively, the clinician may be able toselect multiple groups at one time from group menu 304.

FIG. 21 is a conceptual diagram illustrating an example user interface208 showing user selection of a posture state. In the example of FIG.21, posture state menu 306 of screen 302 is in the drop-down form toallow the clinician to select the desired posture state for whichtherapy adjustment information will be presented. The available posturestates are upright, upright and active, lying back, lying front, lyingright, and lying left. In some examples, if any posture states do nothave associated therapy adjustments for any programs of the selectedgroup, that posture state may either be grayed out or absent fromposture state menu 306. Further, user interface 208 may allow multipleposture states to be selected from posture state menu 306 when multipleposture states can be presented on screen 302. In other examples,posture state menu 306 may be a scrollable list, a text field for theclinician to enter the desired posture state, or some other menu thatallows the clinician to select the desired posture state to bepresented.

FIG. 22 is a conceptual diagram illustrating an example user interface208 showing stored therapy adjustment information 323 for all posturestates and all programs of a program group to allow one-clickprogramming. FIG. 22 is an alternative presentation of therapyadjustment information shown in FIGS. 19-21. As shown in FIG. 22, screen322 of user interface 208 presents therapy adjustment information 323stored during the record mode of therapy. Screen 322 includes group menu324, posture states 326A, 326B, 326C, 326D, 326E, and 326F (collectively“posture state selections 326”), minimum amplitudes 328, programminginformation 330, detail button 332, and summary button 334, andconfirmation button 336.

Group “C” has been selected in group menu 324, so all four programs C1,C2, C3, and C4 are shown for the group. Therapy adjustment information323 includes the minimum amplitude 328 that patient 12 adjusted for eachprogram of the selected group in relation to each of posture stateselections 326. For example, minimum patient-selected amplitudes of 8.0,9.7, 2.2, and 3.8 volts are shown for program C1 when the patientoccupied the upright, upright and active, lying back and lying frontposture states, respectively. Grayed out minimum amplitudes of therapyadjustment information 323, e.g., all minimum amplitudes for lying rightposture state selection 326E, indicate that no therapy adjustments weremade by patient 12 to set the minimum amplitude for that posture stateand group. In this manner, the clinician may identify the posture statesfor which patient 12 has made therapy adjustments. In alternativeexamples, screen 322 may present a different nominal therapy parameterthan minimum amplitudes 328. For example, screen 322 may present maximumamplitudes or the last used amplitudes.

Programming information 330 provides the clinician with information onhow to set the nominal therapy parameters of minimum amplitudes 328 toall of the programs. Specifically, the clinician only needs to click onconfirmation button 336 to program each of the programs C1-C4 with thepresented minimum amplitudes for each posture state. This single clickdramatically reduces the amount of time needed to normally program thenew stimulation parameter for each of the programs in each posturestate. In addition, the clinician may select detail button 332 to viewtherapy adjustment details, as shown in FIG. 23, and summary button 334to view the total number of therapy adjustments for each posture state,as shown in FIG. 24.

FIG. 23 is a conceptual diagram illustrating an example user interface208 showing detailed adjustment information associated with FIG. 22. Asshown in FIG. 23, screen 338 of user interface 208 is navigated to bythe clinician via selection of detail button 332 of screen 322 or someother menu option of user interface 208. Screen 338 presents therapyadjustment information 339 stored within IMD 14 during the record mode.The clinician may select which group to view via group menu 340 and whento return to screen 322 by selecting return button 352.

For each program of the selected group, screen 338 presents posturestates 342A, 342B, 342C, 342D, 342E, and 342F (collectively “posturestate selections 342”). Also, for each program and each posture stateselection 342, minimum amplitudes 344, maximum amplitudes 346, and lastused amplitudes 348 are presented to the clinician. Therefore, theclinician may review the entire range of amplitudes used by patient 12in addition to the last used amplitude that may indicate which directionthe therapy is progressing. As indicated by note 350, grayed outamplitudes may indicate that they have not been adjusted by patient 12.In other examples, screen 338 may present the number of therapyadjustments to each program in each posture state in addition to, orinstead of, last used amplitudes 348. Other information related totherapy adjustments and posture state information may also be presentedin alternative examples of screen 338.

In other examples, the therapy adjustment information may be arrangeddifferently on screen 338. For example, any unadjusted posture statesmay be removed from screen 338 because patient 12 has not used thoseposture states. Alternatively, therapy adjustment information mayinclude a mean or median amplitude for each program and posture stateselection 342. Further, upon the selection of an amplitude withintherapy adjustment information 339, user interface 208 may displayadditional data, such as each therapy adjustment, the time and datestamp of each adjustment, the average adjustment for each day within thelast week, month, year, or entire therapy, or any other detailedamplitude information. In some examples, therapy information may provideadjustments to other therapy parameters, such as pulse width, pulserate, or electrode configuration. Of course, any therapy adjustmentinformation related to drug delivery therapy and IMD 26 may be presentedto the clinician if drug delivery is used instead of or in addition toelectrical stimulation therapy.

FIGS. 24A and 24B are conceptual diagrams illustrating example userinterface 208 that provides maximum and minimum therapy adjustmentsassociated with each posture state in screen 337. Screen 337 of FIG. 24Ais similar to screen 336 of FIG. 23. As shown in FIG. 24A, screen 337provides detailed adjustment information associated with FIG. 22. Asshown in FIG. 23, screen 337 of user interface 208 has been accessed bythe clinician via selection detail button 332 of screen 322 or someother menu option of user interface 208. Screen 337 presents therapyadjustment information 335 stored within IMD 14 during the record mode,including minimum and maximum amplitude settings selected by a user asadjustments to particular therapy programs when the patient occupiedparticular posture states. The clinician may select which group to viewvia group menu 341 and when to return to screen 322 by selecting returnbutton 353. Return button 353 also programs stimulation therapy with theselected therapy values displayed in screen 337.

In the example of FIG. 24A, for each program (C1, C2, C3) of theselected program group (C), screen 337 presents posture states 343A(Upright), 343B (Upright and Mobile), 343C (Lying Back), 343D (LyingFront), 343E (Lying Right), and 343F (Lying Left), collectively posturestate selections 343. Upright and Mobile may be similar to or the sameas an Upright and Active posture state, described elsewhere in thisdisclosure. For each program in the selected group and each posturestate selection 343A-343F, minimum amplitudes 347 and maximum amplitudes349 are presented to the clinician. Therefore, the clinician may reviewthe range of amplitudes used by patient 12 for a particular program whenthe patient occupied a particular posture state. As indicated by note351, the user is reminded that selecting return button 353 enablesposture responsive stimulation for each selected posture state of screen337 using the respective minimum values of the amplitude settings. Inother examples, screen 337 may present the number of therapy adjustmentsto each program in each posture state. Other information related totherapy adjustments and posture state information may also be presentedin alternative examples of screen 337. If a therapy adjustment has notbeen made in a given program, then no minimum or maximum amplitude valuewill be provided in therapy adjustment information 335.

As an illustration, using screen 337, a user may view minimum andmaximum voltage (Min V and Max V) settings for each of programs C1-C3 ofthe selected group C, and for each of several posture states. Byselecting a posture state, e.g., by checking a box such as box 345 forthe Upright posture, the user may indicate whether posture-responsivestimulation (AdaptiveStim) should be delivered with the Min V amplitudesetting indicated for the posture state and program. If the patientselects Upright, by checking box 345, and then selects button 353,posture-responsive therapy will be delivered with the Min V amplitudesetting indicated for each of the programs C1-C3 when the patient isdetermined to be in the Upright posture state. By checking all posturestates, the pertinent Min V amplitude settings may be delivered for eachof programs C1-C3 when the patient is determined to be in the pertinentposture state.

If the user has selected the Upright posture state and then activatedbutton 353, the IMD 14 will be programmed to deliver stimulation with avoltage amplitude of 0.8 volts for the C1 program, 1.05 volts for the C2program, and 0.8 volts for the C3 program when the patient is in theUpright posture state and the selected program group is group C.Likewise, for any other postures that the user has selected, uponactivation of button 353, the programmer will be configured to programthe IMD 14 to deliver applicable minimum voltage amplitudes of theprograms in the selected group when the patient is in the specifiedposture states. Again, in this manner, the minimum voltage settingsselected patient when a particular program group was applied for aparticular posture state will thereafter be applied when the programgroup is applied and the patient again resides in the posture state.Hence, each posture state will have its own amplitude settings forprograms in different program groups, and the amplitude settings areselected based on the minimum settings manually entered by the patientfor the programs when the patient was in the posture state.

In other examples, the therapy adjustment information may be arrangeddifferently on screen 337. For example, any unadjusted posture statesmay be removed from screen 337 because patient 12 has not used thoseposture states. Alternatively, therapy adjustment information mayinclude a mean or median amplitude for each program and posture stateselection 343. Further, upon the selection of an amplitude withintherapy adjustment information 335, user interface 208 may displayadditional data, such as each therapy adjustment, the time and datestamp of each adjustment, the average adjustment for each day within thelast week, month, year, or entire therapy, or any other detailedamplitude information. In some examples, therapy adjustment information335 may provide adjustments to other therapy parameters, such as pulsewidth, pulse rate, or electrode configuration. Of course, any therapyadjustment information 335 related to drug delivery therapy and IMD 26may be presented to the clinician if drug delivery is used instead of orin addition to electrical stimulation therapy.

FIG. 24B illustrates how the user may select a desired group of therapyprograms within screen 337 of user interface 208. Upon selection of thedown arrow of group menu 341, user interface 208 provides the list ofall available therapy groups (e.g., A, B, C, etc.). As shown in FIG.24B, Group C is identified as the current group that defines stimulationtherapy. Upon the selection of the desired group from group menu 341,screen 337 changes to show therapy adjustment information associatedwith the selected group, including minimum and maximum voltage settingsfor the programs in the selected group when the patient occupieddifferent posture states.

FIG. 25A is a conceptual diagram illustrating an example user interface208 showing quantified therapy adjustments 356 for each posture state358. Although therapy adjustments 356 shows as cumulative of all therapyprograms, in other examples, screen 354 may only present adjustments forprograms in a specified therapy group indicated on screen 354. Hence,user interface 208 may present the total number of adjustments for eachposture state for all programs delivered while the patient was in theposture state, or show the total number of adjustments for each posturestate for each program group delivered while the patient was in theposture state. As shown in FIG. 25A, screen 354 of user interface 208 isnavigated to by the clinician via selection of summary button 320 ofscreen 302, detail button 332 of screen 322, or some other menu optionprovided by user interface 208. Screen 354 includes quantified therapyadjustments 356 that include posture states 358 and a correspondingadjustment value 360.

For each of the posture states 358, the clinician may desire to view howmany therapy adjustments were made during the previous time interval orprevious therapy session. Therefore, adjustment values 360 provide thetotal number of therapy adjustments associated with each of the posturestates sensed by IMD 14. Adjustment values 360 may be a total number ofadjustments during therapy, or an average number of adjustments perhour, day, week, month, or any other time interval that may or may notbe selectable by the clinician. In addition, adjustment values 360 maybe averaged over a certain time period by estimating the number of daysor weeks over the therapy session of interest. In the example of FIG.25A, the number of adjustments for the Upright, Upright and Active,Lying Back, Lying Front, Lying Right and Lying Left posture states were38, 11, 19, 41, 21, and 14, respectively, for a given period.

The quantified therapy adjustments 356 may be useful to the clinician indetermining posture states 358 for which patient 12 must manually adjustmore often. Fewer adjustments may indicate that patient 12 is manuallyfinding effective therapy often, while greater adjustments may indicatethat patient 12 may be having difficulty manually finding therapyparameters that define effective therapy. These may be the appropriateinferences when the range of therapy adjustments indicates a large rangeof adjustments, e.g., a large range of voltage or current amplitudes.When the quantified number of adjustments indicated by adjustment value360 is high, the clinician may desire to modify one or more programs tofind a different set of therapy parameters that better treat patient 12,including parameters such as pulse width, pulse rate, electrodecombination and electrode polarity. In this case, amplitude adjustmentsalone may be insufficient to provide effective therapy. In addition,screen 354 may provide trend information that shows if patient 12 hasbeen making more or fewer adjustments over time. For example, screen 354may present a graph or numerical representation of the trend data. Theclinician may then adjust the program therapy parameters accordingly.Once the clinician is finished viewing screen 354, selection of returnbutton 362 may bring the clinician back to a previous screen or to ahome screen or main menu of clinician programmer 60.

As discussed above, a large number of adjustments may indicate a lack ofefficacy when the range of adjustments is large. When the patientreceives stimulation that is not posture state-responsive, a largenumber of adjustments over a small range of adjustments may indicate asituation in which posture state-responsive stimulation should beactivated for the patient. In particular, if posture state-responsivestimulation is not enabled, the number of patient therapy adjustmentsduring delivery of regular stimulation is large, and the range ofpatient therapy adjustments is small, the patient 12 may be a very goodcandidate for delivery of posture state-responsive stimulation therapy.As an illustration, if patient 12 makes numerous adjustments in a narrowvoltage amplitude range of a 4.8 to 5.2 volts for a given posture state,then delivery of posture state-responsive therapy may be desirable forthat posture state.

FIG. 25B is a conceptual diagram illustrating an example user interface355 showing quantified therapy adjustments 357 and 363 for each posturestate in all groups and a specified group, respectively. Therapyadjustments 357 are provided as a cumulative value for adjustments madeduring therapy according to all program groups. Therefore, adjustments361 provides a value for the number of adjustments made while patient 12was engaged in each of posture states 359, regardless of which programwas being used to deliver therapy. The value provided by adjustments 361may be the number of adjustments over the most recent session, e.g.,since the previous clinician visit, or during any other time period.Therapy adjustments 357 may allow the clinician to identify the posturestates 359 for which patient 12 is having difficulty finding theappropriate stimulation therapy parameters. Again, large number ofadjustments over a large range may indicate that the patient 12 ishaving difficulty in tuning the stimulation for the posture, whereas alarge number of adjustments over a small range may indicate that posturestate-responsive therapy is a good fit for the patient for the givenposture state.

Quantified therapy adjustments 363 present adjustments that patient 12has made only during therapy delivered by the selected program groupshown in group menu 371. As shown in FIG. 25B, screen 355 presents thenumber of adjustments 369 for each posture state 367. The user may viewtherapy adjustments for other program groups by selecting a differentgroup from group menu 371. Therapy adjustments 363 may allow theclinician to identify which group is best tailored to treat patient 12by identifying the least number of adjustments. Adjustments 369 mayprovide values that are normalized to the length of time patient 12received therapy with each group so that the clinician may makecomparisons between program groups. In other embodiments, screen 355 mayimmediately present the group with the most adjustments 369 so that theclinician may begin remedying the ineffective therapy, e.g., by makingadjustments to therapy parameters.

As discussed above, the number of patient therapy adjustments can beclustered, e.g., by application of a search timer whereby therapyadjustments that are closely spaced in time reset the search timer andresult in a single, final therapy adjustment as the therapy adjustmentthat is associated with the posture state. In this manner, a number ofclosely spaced adjustments are presented as a single programmingintervention event. Treatment of clustered adjustments as a singleprogramming intervention event may be especially appropriate if thevalues of the adjustments are also close to one another. In someimplementations, rather than clustering therapy adjustments that arereceived closely in time using a search timer or other technique, it maybe desirable to associate all of the individual patient therapyadjustments with a posture state, even if the adjustments are temporallyclose to one another. Accordingly, some implementations may provideclustering of patient therapy adjustments, while other implementationsmay not.

FIG. 26 is a conceptual diagram illustrating an example user interface208 showing quantified therapy adjustment information for all posturestates of a program group to allow one-click programming. FIG. 26 is analternative presentation of therapy adjustment information shown inFIGS. 19-21 or FIGS. 22-25. As shown in FIG. 26, screen 364 of userinterface 208 presents therapy adjustment information 365 stored duringthe record mode of therapy. Screen 365 includes group menu 366, posturestates 368A, 368B, 368C, 368D, 368E, and 368F (collectively “posturestate selections 368”), adjustment values 370, minimum amplitudes 372,programming information 374, and confirmation button 376.

Once the clinician selects the desired group of programs in group menu366 (e.g., group C), screen 364 presents the respective therapyadjustment information 365. Specifically, screen 364 provides anadjustment value 370 and minimum amplitude 372 for each of the programsand posture state selections 368. Again, the minimum amplitude 372represents the minimum value specified by the patient when adjusting theamplitude of a program for a particular posture state. The adjustmentvalue 370 is the number of times that patient 12 adjusted therapy forthe specific program and posture state, and any non-adjustment isindicated with a zero and grayed out minimum amplitude 372. By a singleclick of confirmation button 376, the clinician may set the minimumamplitude as the nominal stimulation parameter to be delivered for eachof the respective program and posture state combinations to be usedsubsequently during therapy. Therapy information 374 reminds theclinician on how to program therapy with confirmation button 376.

FIG. 27 is a flow diagram illustrating an example method for associatingtherapy adjustments with posture states during a record mode. As shownin FIG. 27, the clinician uses clinician programmer 60 to orient theposture state sensor in the IMD to posture states of patient 12 (378).For example, sensed vectors can be obtained for each of a plurality ofposture states, and used as reference coordinate vectors either alone orto define posture state cones or other volumes, such as lying posturedonut- or toroid-like volumes, as described in this disclosure. Next,clinician programmer 60 receives input to initiate the posture staterecord mode that associates therapy adjustments made by the patient toposture states (380). For example, when a sensed vector indicates aparticular posture state, e.g., by reference to cones, vectors, or thelike, and a patient makes a therapy adjustment, that therapy adjustmentmay be associated with the indicated posture state. After all otherprogramming is completed, IMD 14 delivers therapy to patient 12according to the therapy parameters stored as groups of programs (382).

If IMD 14 does not receive a therapy adjustment from patient 12 viapatient programmer 30 (384), IMD 14 continues delivering therapy topatient 12 (382). However, if IMD 14 does receive a therapy adjustmentfrom patient 12 via patient programmer 30 (384), processor 80 of IMD 14associates the therapy adjustment with the appropriate posture state asdetermined by the posture search timer and the posture stability timer(386), or only the posture stability timer in other examples. Inaddition, IMD 14 may immediately modify the therapy based on the patienttherapy adjustment, and deliver the therapy to the patient 12. Processor80 then stores the association in memory 82 of IMD 14 (388) in additionto any other associates made for the same posture state. The storedassociation may be retrieved by an external programmer for viewing by auser such as a clinician, e.g., for use in analysis of therapeuticefficacy and programming of the IMD. IMD 14 then continues deliveringtherapy to patient 12 (382). Alternatively, patient programmer 30 mayperform the associations and/or store the associations instead of IMD14. A clinician programmer 60 may retrieve the associations from patientprogrammer 30.

As a refinement to the process of associating therapy adjustments withposture states during a record mode, IMD 14 and/or an externalprogrammer 20 may be configured to apply a more stringent posture statedetection requirement. A posture state detection process may detect aposture state based on any of the processes described in thisdisclosure, including those described with reference to FIGS. 8A-8C. Asone example, a posture state may be detected if a sensed coordinatevector resides within a specified angle, cosine value, or distance of aparticular reference coordinate vector for a particular posture state.However, a process for associating therapy adjustments with posturestates may require that the sensed coordinate vector be located moreclosely to the reference coordinate vector. In this case, even if aparticular posture is detected based on the location of the sensedcoordinate vector within a first tolerance range of the referencecoordinate vector, patient therapy adjustments are associated with thedetected posture state only if the sensed coordinate vector is locatedwithin a second, tighter tolerance range of the reference coordinatevector. The second range for association is smaller than the first rangefor detection, requiring closer proximity of the sensed coordinatevector to the reference coordinate vector for an association to be made.

Hence, in this alternative implementation, IMD 14 or programmer 20 makesan association between a patient therapy adjustment and a posture stateif a more stringent posture detection criteria is met. For example, inthe example of a cone-based posture detection scheme, where each posturestate is defined by a reference coordinate vector and a cone defining atolerance angle, a patient may be detected as being in the face upposture state if he is plus or minus 30 degrees from the referencecoordinate vector for the face up cone. For purposes of associatingpatient therapy adjustments with posture state, however, IMD 14 orprogrammer 20 makes the association only if the patient is detected inthe face up posture state, and the patient is within plus or minus 15degrees from the coordinate reference vector for the face up posturestate cone.

In a toroid-based detection scheme, the patient would be classified aslying if he is greater than 60 degrees, for example, away from anupright reference coordinate vector or virtual upright referencecoordinate vector. For purposes of association of patient therapyadjustments with posture states, however, IMD 14 or programmer 20 may beconfigured to only associate a therapy adjustment with a lying posturestate if the patient is greater than 75 degrees, for example, from anupright reference coordinate vector or virtual upright referencecoordinate vector. In each of these examples, in determining whether toassociated patient therapy adjustments with posture states, IMD 14 orprogrammer 20 applies association criteria or logic with an increasingspecificity applying a more conservative tolerance criteria than theposture state detection in general.

FIG. 28 is a flow diagram illustrating an example method for displayingsuggested parameters and receiving a confirmation input from the userfor one-click programming. Although clinician programmer 60 is describedwith respect to FIG. 28, any external programmer 20 may be used. Asshown in FIG. 28, clinician programmer 60 first acquires the therapyadjustment information from IMD 14 or patient programmer 30, whichincludes parameter values associated with posture states during therecord mode (390). Each parameter value represents the value of theparameter following a therapy adjustment by the patient. Next, userinterface 208 of clinician programmer 60 receives group input from thegroup menu presented on user interface 208 (392). Processor 104 thencommands user interface 208 to present the nominal therapy parametersfor each program and posture state in a selected group based upon thetherapy adjustments made by patient 12 (394). As described herein, thenominal therapy parameters may be a minimum amplitude, a maximumamplitude, the last used amplitude, or some other parameter selectedfrom the therapy adjustment information.

If user interface 208 receives a confirmation input from the clinicianaccepting the nominal stimulation parameters to be set for all of theprograms (396), then processor 104 sets all programs in the selectedgroup according to the nominal therapy parameters for further use duringdelivery of automatic posture responsive stimulation (398). If there isa navigation input received by user interface 208 (400), the processor104 commands user interface 208 to leave the programming screen (404)and continue programming. Otherwise, user interface 208 again presentsthe nominal therapy parameters (394) if there is no new group selectedby the clinician (402), or user interface 208 detects that the cliniciandesires a new group selection (402) and receives the group input fromthe group menu (392). By presenting nominal values for each program in agroup and for each posture state, a clinician may quickly select andapply the nominal values for use in posture-responsive therapy when thepatient again occupies the pertinent posture states while the IMD isdelivering the pertinent group of programs.

FIG. 29 is a conceptual diagram illustrating an example user interface208 presenting suggested therapy parameters for each program of aprogram group in guided programming. In general, a programmer receivestherapy adjustment information that includes therapy adjustments made bya patient to at least one parameter of one or more stimulation therapyprograms for one or more patient posture states, and generates one ormore suggested therapy parameters for one or more of the stimulationtherapy programs based on the therapy adjustment information. Thesuggested therapy parameters are presented to a user for selection inorder to program therapy parameter values for posture states to supportposture state-responsive therapy.

FIG. 29 is similar to FIG. 19, but screen 406 of FIG. 29 presentssuggested therapy parameters to the clinician. Clinician programmer 60is described, but any external programmer 20 may provide screen 406 tothe user. Example user interface 208 shows suggested therapy parametersfor each program in a group and allows guided programming with a singleconfirmation input. As shown in FIG. 29, screen 406 of user interface208 presents suggested therapy parameters for each program, based uponthe therapy adjustment information stored in IMD 14 and retrieved byclinician programmer 60. Screen 406 also includes group menu 408,posture state menu 410, programs 412, suggested therapy parameters 414,confirmation button 416, and summary button 418.

Group menu 408 allows the clinician to select the desired group ofprograms to be displayed on screen 406. Currently, the clinician hasselected group “C,” which is also the group currently selected (i.e.,active) to deliver stimulation therapy because of the quotation marksaround the group letter. Posture state menu 410 also allows theclinician to select the desired posture state so that the therapyadjustment information that is presented is related to the selectedposture state. In FIG. 29, the clinician has selected the uprightposture state in posture state menu 410.

Each of programs 412 (C1, C2, and C3) is presented with a suggestedtherapy parameter 414 that can be programmed for each of the programs412. The suggested therapy parameter 414 may be generated by theprogrammer based upon the stored therapy adjustment information and aguided algorithm that is used to calculate the most appropriate therapyparameter for patient 12. The guided algorithm may be preprogrammed inmemory 108 of clinician programmer 60 by the manufacturer or preselectedby the clinician to best fit patient 12. The guided algorithm may usethe therapy adjustment information to simply calculate the suggestedtherapy parameter 414 as a mean amplitude, median amplitude, or mostfrequently used amplitude from the therapy adjustments associated withthe program and posture states, or the guided algorithm may perform morecomplex calculations. For example, processor 104 may calculate aweighted low amplitude value to attempt to generate a suggested therapyparameter that provided therapeutic stimulation without over-stimulatingpatient 12. These and other guided algorithms are described further withreference to FIG. 30.

As an illustration, for a given program (e.g., C1_ and a given posturestate (e.g., Upright), programmer 60 may compute a mean amplitude of allof the amplitudes selected by the patient for program C1 as a therapyadjustment when the patient was in the posture state. If there were fourpatient adjustments to program C1 in a given therapy session when thepatient was in the Upright posture state, resulting in voltageamplitudes of 5.0 volts, 5.2 volts, 6.0 volts and 6.2 volts for programC1, then a mean voltage amplitude of 5.6 volts can be selected as thesuggested amplitude to be automatically delivered when program C1 isapplied as the patient is detected as residing in the Upright posturestate. In addition to the mean value, programmer 60 may display theminimum and maximum values even if the user is only permitted to selectthe mean value. In this manner, the user can select the mean value as hesuggested or guided value but still be able to conveniently observe theminimum and maximum values to understand where the guided value fallswithin the min-max range.

As another illustration, for a given program (e.g., C1_ and a givenposture state (e.g., Upright), programmer 60 may determine a mostfrequently selected amplitude of all of the amplitudes selected by thepatient for program C1 as a therapy adjustment when the patient was inthe posture state. If there were ten patient adjustments to program C1in a given therapy session when the patient was in the Upright posturestate, resulting in voltage amplitudes of 5.0 volts, 5.2 volts, 6.0volts, 6.0 volts, 6.0 volts, 5.8 volts, 4.8 volts, 5.5 volts, 6.0 volts,and 6.2 volts for program C1, then a most frequently selected voltageamplitude of 6.0 volts can be selected as the suggested amplitude to beautomatically delivered when program C1 is applied as the patient isdetected as residing in the Upright posture state.

With the suggested therapy parameters 414 presented to the clinician,screen 406 also may allow the clinician to make changes to the therapyparameters of each of the programs shown on screen 406. In the exampleof FIG. 29, the suggested therapy parameter is the mean amplitude of thevalues associated with recorded patient therapy adjustments for thatposture state. The clinician may desire to set all of the programs ofgroup “C” to their mean amplitude by selecting confirmation button 416(“Accept Guided Value”), a confirmation input, only one time. In thismanner, programming time and effort may be decreased because theclinician may only need a single click of confirmation button 416.Alternatively, the clinician may accept the guided value for individualprograms rather than all programs at the same time. By selecting summarybutton 418, clinician programmer 60 will present additional posturestate information or therapy adjustment information via user interface208. The additional posture state information may include the totalnumber of therapy adjustments associated with each posture state, asshown in FIGS. 25A and 25B.

Although screen 406 only shows the programs for one group at a time,alternative examples of user interface 208 may present more than onegroup of programs at one time. Then, the clinician may be able to setmore suggested therapy parameters for multiple groups of programs with asingle click of confirmation button 416. In other examples, theclinician may be able to select a global confirmation button (not shown)that sets the suggested therapy parameter for every program within IMD14 with a single click of the global confirmation button.

FIG. 30 is a conceptual diagram illustrating an example user interface208 showing different guided algorithms selectable by the user forguided programming. Screen 420 is similar to screen 406 of FIG. 29, butscreen 420 allows the clinician to select a guided algorithm. As shownin FIG. 30, screen 420 includes group menu 422, posture state menu 424,guided algorithm menu 426, and confirmation button 428. Programs andsuggested therapy parameters are not shown because they are covered bythe drop-down portion of guided algorithm menu 426. As describedpreviously, group menu 422 allows the selection of a group of programsand posture state menu 424 allows for the selection of a posture state.In addition, once suggested therapy parameters have been generated, theclinician may set all the programs to their respective suggested therapyparameters by a single selection confirmation button 428. However,guided algorithm menu 426 also allows the clinician to customize themethod for generating the suggested therapy parameters.

Guided algorithm menu 426 may be populated with general guidedalgorithms for generating a suggested therapy parameter by themanufacturer, a technician, or the clinician. Guided algorithm menu 426may include one or more guided algorithms. Generally, only one of theguided algorithms may be selected to generate the suggested therapyparameters for each group. Although the clinician may select the sameguided algorithm for setting therapy parameters for each group ofprograms, the clinician may use different guided algorithms fordifferent groups as needed.

Possible guided algorithms include a mean, a median, a safe average, aweighted low average, a weighted high average, a most frequent therapyparameter, a trend target, and a most recently used parameter. A safeaverage may be an average of the lowest half of the therapy parametersto prevent over stimulation. A weighted low average may average alltherapy parameters used, but the lowest third of parameters are weighteddouble, for example. Conversely, a weighted high average may average allparameters used, but the highest third of parameters are weighteddouble, for example. The most frequent therapy parameter is just themost common parameter used by patient 12, while the most recentparameter is just the last used parameter for each program.

The trend target may be a guided algorithm that uses an average thatweights more recently used therapy parameters while even rejectingtherapy parameters that have not been used for a certain amount of time.The trend target may average each therapy parameter used, but only afterreducing the weight of each parameter by a proportional number of daysin the past it was used. For example, for each day old a therapyparameter was recorded, one percent of weight is reduced from theparameter prior to averaging. In this manner, a therapy parameterassociated that day would have full weight, but a therapy parameterassociated fifty days ago would only be given half weight. Therefore,the generated suggested therapy parameter will most resemble more recenttherapy adjustments made by patient 12. A most recently used parameteralgorithm may simply generate, as a suggested therapy parameter, aparameter value associated with a most recently received patient therapyadjustment.

In alternative embodiments, user interface 208 may provide a screen thatallows the clinician to create new guided algorithms or modify currentlystored guided algorithms. The guided algorithms may be stored byclinician programmer 60, patient programmer 30, IMD 14, or any otherdevice. In some examples, clinician programmer 60 may even download newguided algorithms created by the manufacturer, a technician, or otherclinicians over a network.

FIG. 31 is a flow diagram illustrating an example method for generatinga suggested therapy parameter for each therapy program and receiving aconfirmation input from the user. Although clinician programmer 60 isdescribed in FIG. 31, any external programmer 20 may function similarly.As shown in FIG. 31, clinician programmer 60 enters guided programmingwhen requested by the clinician (432). Next, user interface 106 ofclinician programmer 60 receives the posture state and group input thatselects the desired group of programs and posture states (434). Next,processor 104 analyzes the stored therapy adjustment information foreach posture state and program as stored during the record mode (436).In some examples, user interface 106 may also receive a guided algorithminput from the clinician that selects which guided algorithm processor104 uses to generate the suggested therapy parameters.

Based on the guided algorithm set by the manufacturer or selected by theclinician, processor 104 generates a suggested therapy parameter foreach of the plurality of programs (438). Next, user interface 106presents the suggested therapy parameters to the clinician (440). Ifuser interface 106 receives a confirmation input from the clinician toset the suggested therapy parameters to the programs (442), theprocessor 104 sets all the programs with the suggested therapy parameter(446) and determines if the clinician desires another suggestion (448).If user interface 106 does not receive a confirmation from the clinician(442), processor 104 waits to see if the clinician desires anothersuggestion (448). If the clinician desires more suggested therapyparameters (448), user interface 106 waits to receive the posture stateinput and the group input from the clinician (434). Otherwise, processor104 exits the guided programming screen (450).

FIG. 32 is a flow diagram illustrating an example method for correctinga therapy adjustment associated with an unintended posture state. Ingeneral, upon receiving a patient therapy adjustment to a parameter of atherapy program that defines electrical stimulation therapy delivered tothe patient, and identifying a posture state of the patient, aprogrammer may associate the patient therapy adjustment with the posturestate when the patient therapy adjustment is within a range determinedbased on stored adjustment information for the identified posture state.

Patient 12 may make an adjustment to a therapy parameter intending theadjustment for a specific posture state. However, the therapy adjustmentmay not be associated with the desired posture state because thetransitions between posture states causes the stability period, and orsearch period, to fail to capture the desired posture state. The resultin this circumstance is that a therapy adjustment may be associated withan unintended posture. IMD 14 and/or patient programmer 30 may be ableto handle this exception to limit or prevent these unintended therapyadjustment associations. IMD 14 may automatically determine if thetherapy adjustment should be associated with the identified posturestate or IMD 14 may communicate with patient programmer 30 to prompt theuser to confirm that the association is intended by patient 12 and iscorrect.

In the example of FIG. 32, IMD 14 delivers therapy to patient 12 (460)and continues to deliver therapy unless patient programmer 30 receives atherapy adjustment to a therapy parameter of the therapy program frompatient 12 (462). If processor 104 of patient programmer 30 receives atherapy adjustment, processor 104 changes the therapy parameteraccording to the adjustment and then identifies the posture state ofpatient 12 once the stability period expires (464). In some examples,processor 104 of patient programmer 30 may cancel any association if thesearch period expires prior to expiration of the stability period, asdescribed herein.

Once the posture state of patient 12 is identified, processor 104retrieves the stored adjustment information from memory 108 for thetherapy program and identified posture state (466). Processor 104 thenanalyzes the stored adjustment information, and if processor 104determines that the received therapy adjustment is within a historicalrange of the stored adjustment information (468), processor 104 thenassociates the therapy adjustment with the identified posture state(470) and continues to deliver therapy (460). A historical range may bedetermined in a variety of ways.

If the received therapy adjustment is outside of the historical range ofadjustments for the identified posture state (468), then processor 104prompts patient 12 to confirm the association of the therapy adjustmentto the identified posture state (472). If patient 12 confirms that theassociation is correct (474), then processor 104 associates the therapyadjustment to the posture state (470) and continues to deliver therapy(460). If patient 12 does not confirm the association, or rejects theassociation (474), then processor 104 does not associate the therapyadjustment to the identified posture state (476) before continuing todeliver therapy (460).

The historical range used by processor 104 to determine whether thereceived therapy adjustment should be associated with a posture statemay vary based upon the therapy for patient 12 or the desires of theclinician. The historical range may be any range or threshold based uponthe prior adjustments stored for the identified posture state. Forexample, the historical range may simply be bounded by the highest andlowest parameter values for the adjusted parameter. In other examples,the historical range may include an upper threshold or lower thresholdto prevent an unintended parameter value association that could causeuncomfortable or even painful stimulation if posture responsivestimulation is enabled.

Alternatively, the historical range may be a calculated historical rangethat weights recent parameter adjustments greater than older parameteradjustments of the adjustment information made by patient 12 in theposture state. For example, previous patient adjustments can be dividedinto a lower set of patient adjustments and a higher set of patienttherapy adjustments, e.g., as determined by parameter values associatedwith such adjustments, such as voltage or current amplitude

An upper bound of the range may be set according to an average of thehigher set of patient therapy adjustments, and a lower bound of therange may be set according to an average of the lower set of patientadjustments. If the prior patient therapy adjustments include amplitudevalues of 4.0, 4.2, 4.4, 5.0, 5.2, 5.6, 6.0 and 6.2 volts, for example,the upper bound could be computed as an average of the four largestvalues (5.2, 5.6, 6.0 and 6.2), and the lower bound could be computed asan average of the four lowest values (4.0, 4.2, 4.4, 5.0) In some cases,the lower and upper patient therapy adjustments may be weighted so thatmore recent patient therapy adjustments are weighted more heavily thanless recent patient therapy adjustments in calculating the upper andlower bounds of the range. This weighted historical range wouldessentially limit the historical range to more recent parameter valuesused by patient 12. In each case, the range may be inclusive of at leasta subset of the previous patient therapy adjustments for the program andthe posture, but may be effective in avoiding unintended associations ofoutliers.

As another example, a range may be determined by determining an average,median or mean of previous patient therapy adjustments and thenestablishing threshold bounds above and below the average, median ormean. The thresholds may be symmetrical about the average, median ormean, or asymmetrical. If an average voltage amplitude is 5.0 volts, forexample, lower and upper threshold bounds could be placed at 4.0 and 6.0volts, and patient therapy adjustments outside of that range would bedisregarded and not associated with pertinent program and posture state.In this case, the upper and lower bounds are placed symmetrically aboutthe average. Alternatively, the upper and lower bounds could be placedasymmetrically such that one bound is closer to the average than theother bound.

In some cases, the threshold bounds may be computed as a percentage ofthe average. In the above example, the upper and lower bounds of 6.0volts and 4.0 volts are plus/minus 20 percent of the average of 5.0volts. As described above, in some cases, average may be an average ofweighted values so that more recent patient therapy adjustments areweighted more heavily than less recent patient therapy adjustments incalculating the average, and ultimately the upper and lower bounds ofthe range, which may be centered or not centered about the averagevalue. Again, this weighted historical range would limit the historicalrange to more recent parameter values used by patient 12.

Further, the historical range may be determined at least in part by aperception threshold and a pain threshold for the parameterpredetermined by the clinician for patient 12. For example, the upperbound is set to be at or below a pain threshold and the lower bound isset to be at or above the perception threshold. In this case, patienttherapy adjustments that result in parameter values below a perceptionthreshold or above a pain threshold, each of which may be established inclinic, may be disregarded and not associated with a particular programand posture state, e.g., on the basis that such patient therapyadjustments may have been unintended for association with the posturestate.

Any type of range may be used to trigger confirmation by patient 12before an association is made, and the range may be set uponinitialization of therapy or changed during stimulation therapy topatient 12. In any case, the historical range calculated by processor104 is inclusive of therapy adjustments that would be acceptable for theparticular identified posture state. For example, the range may beinclusive of at least a subset of previous therapy adjustments for theprogram and posture state. In some cases, the range could even allow forpatient therapy adjustments that are within a predetermined marginoutside of the previous patient therapy adjustments. Unacceptabletherapy adjustments are those therapy adjustments that would not bedesirable by patient 12 and/or outside of previously used therapyparameter values stored as the therapy adjustment information.

As described above, ranges to avoid unintended associations withprograms and postures states may be computed, calculated, or otherwisedetermined in a variety of ways. Also, as new patient therapyadjustments are received, the range may be updated to take into accountthe values of the new patient therapy adjustments. In some cases, eventhough a new patient therapy adjustment falls outside of the currentrange, and therefore is not associated with a program and posture state(or at least requires patient confirmation to make the association), thenew patient therapy adjustment could still be used to update the currentrange, i.e., as one of the values used to produce an average, weightedaverage or other range calculation.

In other examples, IMD 14 and/or patient programmer 30 may automaticallyremove unintended therapy adjustment associations without any input frompatient 12. If the received therapy adjustment is outside of thehistorical range, processor 104, for example, may simply prevent thatadjustment from being associated with the current program and identifiedposture state without requiring a confirmation from patient 12. In thismanner, patient 12 may not be burdened by continually interacting withpatient programmer 30. Alternatively, the therapy adjustments determinedas unintended may be stored in a separate category such that theclinician may access the unintended therapy adjustments when reviewingthe efficacy of therapy. Further, patient programmer 30 may promptpatient 12 to review how to adjust therapy or to visit the clinicianafter a certain number of unintended associations or a high frequency ofunintended associations.

This disclosure may provide multiple features to a user. For example,implementing a posture search timer and a posture stability timer allowsthe system to correctly associate therapy adjustments to posture stateseven when the patient does not make the therapy adjustment while engagedin the intended posture state. Further, storing each association oftherapy adjustments to posture states allows a clinician to review whenthe patient is adjusting stimulation therapy. This information may allowthe clinician to modify the stimulation therapy in order to find themost effective therapy.

In addition, the disclosure provides a system that can use theassociations between therapy adjustments and posture states in order toaid the clinician in quickly programming stimulation parameters for aplurality of therapy programs in a program group. For example, thesystem may set all therapy programs to the minimum amplitude used by thepatient during stimulation therapy with one confirmation by the user.Moreover, the user interface may present a suggested parameter value foreach of the therapy programs based upon the associations and a guidealgorithm. In this manner, the user may select to confirm all suggestedparameter values with one confirmation input in decrease the amount oftime needed to program or modify the stimulation therapy.

The techniques described in this disclosure may be implemented, at leastin part, in hardware, software, firmware or any combination thereof. Forexample, various aspects of the techniques may be implemented within oneor more microprocessors, digital signal processors (DSPs), applicationspecific integrated circuits (ASICs), field programmable gate arrays(FPGAs), or any other equivalent integrated or discrete logic circuitry,as well as any combinations of such components, embodied in programmers,such as physician or patient programmers, stimulators, or other devices.The term “processor” or “processing circuitry” may generally refer toany of the foregoing logic circuitry, alone or in combination with otherlogic circuitry, or any other equivalent circuitry.

When implemented in software, the functionality ascribed to the systemsand devices described in this disclosure may be embodied as instructionson a computer-readable medium such as random access memory (RAM),read-only memory (ROM), non-volatile random access memory (NVRAM),electrically erasable programmable read-only memory (EEPROM), FLASHmemory, magnetic media, optical media, or the like. The instructions maybe executed to cause one or more processors to support one or moreaspects of the functionality described in this disclosure.

In addition, it should be noted that the systems described herein maynot be limited to treatment of a human patient. In alternativeembodiments, these systems may be implemented in non-human patients,e.g., primates, canines, equines, pigs, and felines. These animals mayundergo clinical or research therapies that my benefit from the subjectmatter of this disclosure.

Many embodiments of the invention have been described. Variousmodifications may be made without departing from the scope of theclaims. These and other embodiments are within the scope of thefollowing claims.

The invention claimed is:
 1. A method comprising: receiving a patient therapy adjustment to a parameter of electrical stimulation therapy delivered to the patient; identifying a posture state of the patient; and associating, by a processor, the patient therapy adjustment with the posture state when the patient therapy adjustment is within a range determined based on stored adjustment information for the identified posture state.
 2. The method of claim 1, further comprising associating the therapy adjustment with the identified posture state when the therapy adjustment is outside of the range based on confirmation that the therapy adjustment is associated with the identified posture state.
 3. The method of claim 2, further comprising receiving the confirmation from the patient.
 4. The method of claim 3, further comprising prompting the patient to confirm or reject the association via a user interface.
 5. The method of claim 1, wherein the adjustment information includes previous patient therapy adjustments for the program and the posture state, the method further comprising determining the range to be inclusive of at least a subset of the previous patient therapy adjustments for the program and the posture state.
 6. The method of claim 5, further comprising setting a minimum value of the range to a lowest value of the previous patient therapy adjustments and setting a maximum value of the range to a highest value of the previous patient therapy adjustments.
 7. The method of claim 5, wherein the range includes an upper threshold determined by an average of highest values of the previous patient therapy adjustments, and a lower threshold determined by an average of lowest values of the previous patient therapy adjustments.
 8. The method of claim 5, further comprising determining the range based at least in part on a weighted average of previous patient therapy adjustments, wherein more recent therapy adjustments are weighted more highly than less recent therapy adjustments.
 9. The method of claim 1, wherein identifying the posture state comprises identifying the posture state if the posture state does not change for a predetermined period of time following sensing of the posture state.
 10. The method of claim 1, further comprising updating the range based on a newly received patient therapy adjustment.
 11. A system comprising: a user interface that receives a patient therapy adjustment to a parameter of electrical stimulation therapy delivered to the patient; and a processor that: identifies a posture state of the patient; and associates the patient therapy adjustment with the posture state when the patient therapy adjustment is within a range determined based on stored adjustment information for the identified posture state.
 12. The system of claim 11, wherein the processor associates the therapy adjustment with the identified posture state when the therapy adjustment is outside of the range based on confirmation that the therapy adjustment is associated with the identified posture state.
 13. The system of claim 12, wherein the user interface receives the confirmation from the patient.
 14. The system of claim 13, wherein the user interface prompts the patient to confirm or reject the association via a user interface.
 15. The system of claim 11, wherein the adjustment information includes previous patient therapy adjustments for the program and the posture state, and the processor determines the range to be inclusive of at least a subset of the previous patient therapy adjustments for the program and the posture state.
 16. The system of claim 15, wherein the processor sets a minimum value of the range to a lowest value of the previous patient therapy adjustments and sets a maximum value of the range to a highest value of the previous patient therapy adjustments.
 17. The system of claim 15, wherein the range includes an upper threshold determined by an average of highest values of the previous patient therapy adjustments, and a lower threshold determined by an average of lowest values of the previous patient therapy adjustments.
 18. The system of claim 15, wherein the processor determines the range based at least in part on a weighted average of previous patient therapy adjustments, wherein more recent therapy adjustments are weighted more highly than less recent therapy adjustments.
 19. The system of claim 11, wherein the processor identifies the posture state if the posture state does not change for a predetermined period of time following sensing of the posture state.
 20. The system of claim 11, wherein the processor updates the range based on a newly received patient therapy adjustment.
 21. The system of claim 11, further comprising an implantable medical device that delivers the defined stimulation therapy to the patient.
 22. A system comprising: means for receiving a patient therapy adjustment to a parameter of electrical stimulation therapy delivered to the patient; means for identifying a posture state of the patient; and means for associating the patient therapy adjustment with the posture state when the patient therapy adjustment is within a range determined based on stored adjustment information for the identified posture state.
 23. The system of claim 22, further comprising means for associating the therapy adjustment with the identified posture state when the therapy adjustment is outside of the range based on confirmation that the therapy adjustment is associated with the identified posture state.
 24. The system of claim 23, further comprising means for receiving the confirmation from the patient.
 25. The system of claim 24, further comprising means for prompting the patient to confirm or reject the association via a user interface.
 26. The system of claim 22, wherein the adjustment information includes previous patient therapy adjustments for the program and the posture state, the system further comprising means for determining the range to be inclusive of at least a subset of the previous patient therapy adjustments for the program and the posture state.
 27. The system of claim 26, further comprising means for setting a minimum value of the range to a lowest value of the previous patient therapy adjustments and means for setting a maximum value of the range to a highest value of the previous patient therapy adjustments.
 28. The system of claim 26, wherein the range includes an upper threshold determined by an average of highest values of the previous patient therapy adjustments, and a lower threshold determined by an average of lowest values of the previous patient therapy adjustments.
 29. The system of claim 26, further comprising means for determining the range based at least in part on a weighted average of previous patient therapy adjustments, wherein more recent therapy adjustments are weighted more highly than less recent therapy adjustments.
 30. The system of claim 22, wherein identifying the posture state comprises means for identifying the posture state if the posture state does not change for a predetermined period of time following sensing of the posture state.
 31. The system of claim 22, further comprising means for updating the range based on a newly received patient therapy adjustment.
 32. The method of claim 1, wherein receiving the patient therapy adjustment comprises receiving, by an implantable medical device, the adjustment from an external programmer.
 33. The method of claim 1, wherein receiving the patient therapy adjustment comprises receiving, by an external programmer, the adjustment from a user interface of the external programmer.
 34. The system of claim 11, further comprising an implantable medical device that houses the processor.
 35. The system of claim 11, further comprising an external programmer comprising the user interface and the processor. 